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At least 919 records · Page 51
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Zn3Fe2Cu10(SnSe4)5 by Materials Project

Fe2Cu10Zn3(SnSe4)5 is Clathrate-derived structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Fe3+ is bonded to four Se2- atoms to form FeSe4 tetrahedra that share corners with four SnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are two shorter (2.43 Å) and two longer (2.44 Å) Fe–Se bond lengths. There are five inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with four CuSe4 tetrahedra, corners with four ZnSe4 tetrahedra, and corners with four SnSe4 tetrahedra. All Cu–Se bond lengths are 2.43 Å. In the second Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share a cornercorner with one FeSe4 tetrahedra, corners with three equivalent ZnSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.42–2.44 Å. In the third Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with four CuSe4 tetrahedra, corners with four ZnSe4 tetrahedra, and corners with four equivalent SnSe4 tetrahedra. All Cu–Se bond lengths are 2.43 Å. In the fourth Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share a cornercorner with one ZnSe4 tetrahedra, corners with three equivalent FeSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.43–2.45 Å. In the fifth Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with four equivalent FeSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are three shorter (2.44 Å) and one longer (2.45 Å) Cu–Se bond lengths. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share corners with four SnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. All Zn–Se bond lengths are 2.50 Å. In the second Zn2+ site, Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share corners with four equivalent SnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. All Zn–Se bond lengths are 2.50 Å. There are three inequivalent Sn+3.60+ sites. In the first Sn+3.60+ site, Sn+3.60+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with two equivalent FeSe4 tetrahedra, corners with two equivalent ZnSe4 tetrahedra, and corners with eight CuSe4 tetrahedra. There are one shorter (2.65 Å) and three longer (2.66 Å) Sn–Se bond lengths. In the second Sn+3.60+ site, Sn+3.60+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with four ZnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are three shorter (2.63 Å) and one longer (2.64 Å) Sn–Se bond lengths. In the third Sn+3.60+ site, Sn+3.60+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with four equivalent FeSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are two shorter (2.67 Å) and two longer (2.68 Å) Sn–Se bond lengths. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to one Fe3+, two Cu1+, and one Sn+3.60+ atom to form corner-sharing SeFeCu2Sn tetrahedra. In the second Se2- site, Se2- is bonded to two Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the third Se2- site, Se2- is bonded to two Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the fourth Se2- site, Se2- is bonded to two Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the fifth Se2- site, Se2- is bonded to one Fe3+, two equivalent Cu1+, and one Sn+3.60+ atom to form corner-sharing SeFeCu2Sn tetrahedra. In the sixth Se2- site, Se2- is bonded to two Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the seventh Se2- site, Se2- is bonded to two equivalent Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the eighth Se2- site, Se2- is bonded to two Cu1+, one Zn2+, and one Sn+3.60+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the ninth Se2- site, Se2- is bonded to one Fe3+, two Cu1+, and one Sn+3.60+ atom to form corner-sharing SeFeCu2Sn tetrahedra. In the tenth Se2- site, Se2- is bonded to one Fe3+, two Cu1+, and one Sn+3.60+ atom to form corner-sharing SeFeCu2Sn tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Enterprise: Exploration of Concepts, Perspectives and Implications for Systems Engineering

The purpose of this paper is to explore the concept of ‘enterprise’ in the context of Systems Engineering (SE). The term ‘enterprise’ has been used extensively to generally describe large complex entities that have an extensive scope of operations. However, a deeper examination of ‘enterprise’ significance for SE can provide insights as our challenges continue with increasingly complex, uncertain, ambiguous, and integrated entities struggling to thrive in the future. The paper explores three central topics. First, the concept of enterprise is introduced as a central aspect of the future focus for SE, as recognized in the INCOSE SE Vision 2035. Second, a more detailed examination of the enterprise concept is developed in relationship to SE. The thrust of this examination is to understand the nature and role of ‘enterprise’ across a broad spectrum of literature and knowledge, ultimately providing a more informed perspective of enterprise for SE. As part of this exploration, a bibliometric analysis of the term ‘enterprise’ is performed. This exploration extracts key themes (clusters) in the ‘enterprise’ literature. Third, challenges for further development and inculcation of ‘enterprise’ within the SE discipline and support for realization of the SE 2035 Vision are suggested. These challenges point out the need to ‘think differently’ about ‘enterprise’ within the SE context. ‘Enterprise’ is proposed as a central, albeit different, perspective for the SE discipline. Finally, the paper closes with a first–generation perspective for ‘enterprise’ in pursuit of the SE Vision 2035.

42 ENGINEERING↗
DOE OSTI2024

Selenium interaction with iron minerals: Quantitative comparison of sorption and coprecipitation impacts on mobility

Given the significance of selenium (Se) as a micronutrient, the radioactive nature of some of its isotopes, and its affinity to iron (Fe) minerals, extensive research has been conducted on the sorption mechanisms between Se and these minerals. Here, in this study, we employ sorption data sourced from the L-SCIE database and coprecipitation data from available literature to achieve the following objectives: i) establish coherence between adsorption and coprecipitation processes, ii) quantitatively evaluate the importance of these processes in nuclear waste repository science, and iii) propose a forward-looking approach for integrating coprecipitation into reactive transport models. Our findings indicate that a correlation between Se adsorption and coprecipitation can be established using the λ formalism. The comparable log(λ Se(IV) /λ Se(VI) ) ratios derived from adsorption and coprecipitation experiments suggest that these processes can be quantitatively compared and evaluated using our numerical approach. Across all iron oxide phases examined, coprecipitation leads to significantly greater immobilization of Se compared to adsorption. Specifically, for hydrous ferric oxide, hematite, and goethite, coprecipitation is predicted to result in 100–1000 times more Se immobilization compared to adsorption, irrespective of the Se oxidation state (Se(IV) or Se(VI)); notably stronger immobilization potential via coprecipitation was observed for magnetite. The modeling approach and quantitative analysis presented herein clearly highlight the importance of including coprecipitation processes when simulating Se (and other elements) transport, particularly under conditions where mineral compositions are transient or evolving with time. Neglecting coprecipitation in models is likely to lead to significant overestimates of migration.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2020

Materials Data on LaSe2 by Materials Project

LaSe2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. La3+ is bonded in a 7-coordinate geometry to seven Se+1.50- atoms. There are a spread of La–Se bond distances ranging from 2.94–3.27 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded in a 4-coordinate geometry to four equivalent La3+ atoms. In the second Se+1.50- site, Se+1.50- is bonded in a 4-coordinate geometry to three equivalent La3+ and one Se+1.50- atom. The Se–Se bond length is 2.50 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba4Sb4Se11 by Materials Project

Ba4Sb4Se11 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to eight Se2- atoms to form distorted BaSe8 hexagonal bipyramids that share a cornercorner with one BaSe8 hexagonal bipyramid, a cornercorner with one SbSe6 octahedra, a cornercorner with one SbSe5 square pyramid, edges with two equivalent BaSe8 hexagonal bipyramids, edges with two equivalent SbSe6 octahedra, and faces with three equivalent BaSe8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 55°. There are a spread of Ba–Se bond distances ranging from 3.32–3.61 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Ba–Se bond distances ranging from 3.39–3.74 Å. There are four inequivalent Sb+3.50+ sites. In the first Sb+3.50+ site, Sb+3.50+ is bonded to six Se2- atoms to form distorted SbSe6 octahedra that share corners with two equivalent BaSe8 hexagonal bipyramids, corners with two equivalent SbSe5 square pyramids, edges with four equivalent BaSe8 hexagonal bipyramids, and an edgeedge with one SbSe6 octahedra. There are a spread of Sb–Se bond distances ranging from 2.61–3.25 Å. In the second Sb+3.50+ site, Sb+3.50+ is bonded in a 3-coordinate geometry to three Se2- atoms. All Sb–Se bond lengths are 2.62 Å. In the third Sb+3.50+ site, Sb+3.50+ is bonded to five Se2- atoms to form SbSe5 square pyramids that share corners with two equivalent BaSe8 hexagonal bipyramids and corners with two equivalent SbSe6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are a spread of Sb–Se bond distances ranging from 2.58–3.06 Å. In the fourth Sb+3.50+ site, Sb+3.50+ is bonded in a distorted trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.61 Å) and two longer (2.65 Å) Sb–Se bond lengths. There are nine inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four equivalent Ba2+ and one Se2- atom. The Se–Se bond length is 2.42 Å. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to three Ba2+ and two Sb+3.50+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to four equivalent Ba2+ and one Sb+3.50+ atom. In the fourth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ba2+ and two equivalent Sb+3.50+ atoms. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to four equivalent Ba2+, one Sb+3.50+, and one Se2- atom. The Se–Se bond length is 2.48 Å. In the sixth Se2- site, Se2- is bonded to four equivalent Ba2+ and one Sb+3.50+ atom to form a mixture of distorted edge and corner-sharing SeBa4Sb square pyramids. In the seventh Se2- site, Se2- is bonded in a 4-coordinate geometry to one Ba2+ and three Sb+3.50+ atoms. In the eighth Se2- site, Se2- is bonded to four Ba2+ and one Sb+3.50+ atom to form a mixture of distorted edge and corner-sharing SeBa4Sb square pyramids. In the ninth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Ba2+ and one Sb+3.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr4Bi6Se13 by Materials Project

Sr4Bi6Se13 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six Se2- atoms to form SrSe6 octahedra that share corners with four BiSe6 octahedra, edges with two equivalent SrSe6 octahedra, and edges with four BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–59°. There are a spread of Sr–Se bond distances ranging from 3.04–3.13 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Sr–Se bond distances ranging from 3.21–3.40 Å. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Sr–Se bond distances ranging from 3.19–3.59 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Sr–Se bond distances ranging from 3.19–3.47 Å. There are six inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Bi–Se bond distances ranging from 2.81–3.17 Å. In the second Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with two equivalent BiSe6 octahedra, edges with two equivalent SrSe6 octahedra, and edges with seven BiSe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of Bi–Se bond distances ranging from 2.76–3.32 Å. In the third Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share a cornercorner with one SrSe6 octahedra, corners with four BiSe6 octahedra, edges with two equivalent SrSe6 octahedra, and edges with eight BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–6°. There are a spread of Bi–Se bond distances ranging from 2.77–3.24 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Bi–Se bond distances ranging from 2.83–3.10 Å. In the fifth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of distorted edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Bi–Se bond distances ranging from 2.75–3.57 Å. In the sixth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with three equivalent SrSe6 octahedra and edges with six BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 58–59°. There are a spread of Bi–Se bond distances ranging from 2.90–3.03 Å. There are thirteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four Sr2+ and one Bi3+ atom to form distorted SeSr4Bi square pyramids that share a cornercorner with one SeSrBi5 octahedra, corners with four SeSr4Bi square pyramids, corners with two equivalent SeSr2Bi3 trigonal bipyramids, corners with two equivalent SeSrBi3 trigonal pyramids, edges with four SeSrBi5 octahedra, and edges with four SeSr4Bi square pyramids. The corner-sharing octahedral tilt angles are 1°. In the second Se2- site, Se2- is bonded to four Sr2+ and one Bi3+ atom to form distorted SeSr4Bi square pyramids that share corners with four SeSr4Bi square pyramids, corners with three equivalent SeSr2Bi3 trigonal bipyramids, edges with two equivalent SeSrBi5 octahedra, edges with four SeSr4Bi square pyramids, and edges with two equivalent SeSr2Bi3 trigonal bipyramids. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Sr2+ and two equivalent Bi3+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Sr2+ and three Bi3+ atoms. In the fifth Se2- site, Se2- is bonded to four Sr2+ and one Bi3+ atom to form distorted SeSr4Bi square pyramids that share a cornercorner with one SeSrBi5 octahedra, corners with six SeSr4Bi square pyramids, edges with two equivalent SeSrBi5 octahedra, edges with five SeSr4Bi square pyramids, and edges with four SeSr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. In the sixth Se2- site, Se2- is bonded to one Sr2+ and five Bi3+ atoms to form distorted SeSrBi5 octahedra that share corners with three SeSr4Bi square pyramids, corners with three SeSr2Bi3 trigonal bipyramids, edges with four equivalent SeSrBi5 octahedra, edges with four SeSr2Bi3 square pyramids, and edges with three equivalent SeSr2Bi3 trigonal bipyramids. In the seventh Se2- site, Se2- is bonded to four Sr2+ and one Bi3+ atom to form distorted SeSr4Bi square pyramids that share corners with three SeSrBi5 octahedra, corners with six SeSr2Bi3 square pyramids, corners with two equivalent SeSrBi3 trigonal pyramids, edges with two equivalent SeSrBi5 octahedra, edges with five SeSr4Bi square pyramids, and edges with two equivalent SeSr2Bi3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 4–47°. In the eighth Se2- site, Se2- is bonded to two Sr2+ and three Bi3+ atoms to form distorted SeSr2Bi3 trigonal bipyramids that share corners with three SeSrBi5 octahedra, corners with three SeSr2Bi3 square pyramids, corners with three SeSr2Bi3 trigonal bipyramids, edges with three equivalent SeSrBi5 octahedra, and edges with four SeSr4Bi square pyramids. The corner-sharing octahedra tilt angles range from 7–41°. In the ninth Se2- site, Se2- is bonded to two equivalent Sr2+ and three Bi3+ atoms to form distorted SeSr2Bi3 square pyramids that share corners with four SeSr4Bi square pyramids, corners with three SeSr2Bi3 trigonal bipyramids, corners with four equivalent SeSrBi3 trigonal pyramids, edges with two equivalent SeSrBi5 octahedra, edges with four SeSr4Bi square pyramids, and an edgeedge with one SeSrBi3 trigonal pyramid. In the tenth Se2- site, Se2- is bonded to one Sr2+ and three equivalent Bi3+ atoms to form distorted SeSrBi3 trigonal pyramids that share a cornercorner with one SeSrBi5 octahedra, corners with eight SeSr4Bi square pyramids, corners with two equivalent SeSrBi3 trigonal pyramids, an edgeedge with one SeSr2Bi3 square pyramid, and edges with two equivalent SeSrBi3 trigonal pyramids. The corner-sharing octahedral tilt angles are 2°. In the eleventh Se2- site, Se2- is bonded to one Sr2+ and five Bi3+ atoms to form SeSrBi5 octahedra that share corners with two equivalent SeSrBi5 octahedra, a cornercorner with one SeSr4Bi square pyramid, a cornercorner with one SeSr2Bi3 trigonal bipyramid, edges with five SeSrBi5 octahedra, edges with four SeSr4Bi square pyramids, and edges with two equivalent SeSr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°. In the twelfth Se2- site, Se2- is bonded to one Sr2+ and five Bi3+ atoms to form SeSrBi5 octahedra that share corners with two equivalent SeSrBi5 octahedra, a cornercorner with one SeSr4Bi square pyramid, corners with two equivalent SeSr2Bi3 trigonal bipyramids, a cornercorner with one SeSrBi3 trigonal pyramid, edges with seven SeSrBi5 octahedra, edges with four SeSr4Bi square pyramids, and an edgeedge with one SeSr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 5°. In the thirteenth Se2- site, Se2- is bonded to two Sr2+ and three Bi3+ atoms to form distorted SeSr2Bi3 trigonal bipyramids that share corners with three SeSrBi5 octahedra, corners with five SeSr2Bi3 square pyramids, corners with three SeSr2Bi3 trigonal bipyramids, edges with three SeSrBi5 octahedra, and edges with four SeSr4Bi square pyramids. The corner-sharing octahedra tilt angles range from 7–42°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl5(Cu7Se5)2 by Materials Project

Tl5Cu14Se10 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are seven inequivalent Cu+1.07+ sites. In the first Cu+1.07+ site, Cu+1.07+ is bonded in a trigonal planar geometry to three Se2- atoms. There are two shorter (2.47 Å) and one longer (2.49 Å) Cu–Se bond lengths. In the second Cu+1.07+ site, Cu+1.07+ is bonded in a trigonal planar geometry to three Se2- atoms. There are two shorter (2.47 Å) and one longer (2.51 Å) Cu–Se bond lengths. In the third Cu+1.07+ site, Cu+1.07+ is bonded in a distorted trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.38 Å) and two longer (2.51 Å) Cu–Se bond lengths. In the fourth Cu+1.07+ site, Cu+1.07+ is bonded to four Se2- atoms to form a mixture of distorted corner and edge-sharing CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.40–2.69 Å. In the fifth Cu+1.07+ site, Cu+1.07+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.40–2.76 Å. In the sixth Cu+1.07+ site, Cu+1.07+ is bonded to four Se2- atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.48–2.58 Å. In the seventh Cu+1.07+ site, Cu+1.07+ is bonded in a distorted trigonal planar geometry to three Se2- atoms. There are one shorter (2.40 Å) and two longer (2.54 Å) Cu–Se bond lengths. There are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.27–3.73 Å. In the second Tl1+ site, Tl1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.34–3.57 Å. In the third Tl1+ site, Tl1+ is bonded in a body-centered cubic geometry to eight Se2- atoms. There are four shorter (3.37 Å) and four longer (3.47 Å) Tl–Se bond lengths. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four equivalent Tl1+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to six Cu+1.07+ and three Tl1+ atoms. In the third Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four Tl1+ atoms. In the fourth Se2- site, Se2- is bonded in a 9-coordinate geometry to six Cu+1.07+ and three Tl1+ atoms. In the fifth Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four Tl1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb2Bi8Se13 by Materials Project

Rb2Bi8Se13 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.57–4.02 Å. In the second Rb1+ site, Rb1+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.60–3.90 Å. There are eight inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to five Se2- atoms to form BiSe5 square pyramids that share corners with two equivalent BiSe6 octahedra and edges with four equivalent BiSe5 square pyramids. The corner-sharing octahedral tilt angles are 68°. There are a spread of Bi–Se bond distances ranging from 2.73–3.00 Å. In the second Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Bi–Se bond distances ranging from 2.84–3.16 Å. In the third Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 3–7°. There are a spread of Bi–Se bond distances ranging from 2.93–3.06 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 3–10°. There are a spread of Bi–Se bond distances ranging from 2.78–3.23 Å. In the fifth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with three BiSe6 octahedra, corners with two equivalent BiSe5 square pyramids, and edges with five BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 10–15°. There are a spread of Bi–Se bond distances ranging from 2.76–3.29 Å. In the sixth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 5–15°. There are a spread of Bi–Se bond distances ranging from 2.81–3.27 Å. In the seventh Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 7–9°. There are a spread of Bi–Se bond distances ranging from 2.80–3.24 Å. In the eighth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of Bi–Se bond distances ranging from 2.80–3.13 Å. There are thirteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to one Rb1+ and three equivalent Bi3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Rb1+ and three Bi3+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three Rb1+ and two equivalent Bi3+ atoms. In the fourth Se2- site, Se2- is bonded to five Bi3+ atoms to form SeBi5 square pyramids that share a cornercorner with one SeBi6 octahedra, corners with two equivalent SeRbBi4 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, edges with two equivalent SeBi5 square pyramids, and edges with three SeRbBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. In the fifth Se2- site, Se2- is bonded to one Rb1+ and four Bi3+ atoms to form distorted SeRbBi4 trigonal bipyramids that share corners with five SeRb2Bi4 octahedra, corners with two equivalent SeRbBi4 trigonal bipyramids, edges with three SeBi6 octahedra, and edges with two equivalent SeBi5 square pyramids. The corner-sharing octahedra tilt angles range from 7–32°. In the sixth Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Rb1+ and two equivalent Bi3+ atoms. In the seventh Se2- site, Se2- is bonded to six Bi3+ atoms to form SeBi6 octahedra that share corners with three SeRb2Bi4 octahedra, a cornercorner with one SeBi5 square pyramid, edges with nine SeBi6 octahedra, and edges with two equivalent SeRbBi4 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 3–8°. In the eighth Se2- site, Se2- is bonded to two equivalent Rb1+ and four Bi3+ atoms to form distorted SeRb2Bi4 octahedra that share corners with two equivalent SeBi6 octahedra, corners with four SeRbBi4 trigonal bipyramids, and edges with seven SeBi6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the ninth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Rb1+ and two equivalent Bi3+ atoms. In the tenth Se2- site, Se2- is bonded to six Bi3+ atoms to form SeBi6 octahedra that share a cornercorner with one SeBi6 octahedra, corners with two equivalent SeRbBi4 trigonal bipyramids, edges with six SeBi6 octahedra, edges with two equivalent SeBi5 square pyramids, and edges with three SeRbBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 8°. In the eleventh Se2- site, Se2- is bonded to two equivalent Rb1+ and three equivalent Bi3+ atoms to form distorted SeRb2Bi3 trigonal bipyramids that share a cornercorner with one SeRbBi4 trigonal bipyramid and edges with six SeRb2Bi3 trigonal bipyramids. In the twelfth Se2- site, Se2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the thirteenth Se2- site, Se2- is bonded to one Rb1+ and four Bi3+ atoms to form distorted SeRbBi4 trigonal bipyramids that share a cornercorner with one SeRb2Bi4 octahedra, corners with two equivalent SeBi5 square pyramids, corners with three SeRb2Bi3 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, an edgeedge with one SeBi5 square pyramid, and edges with two equivalent SeRb2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 13°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na4TiSe4 by Materials Project

Na4TiSe4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are eight inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with four NaSe6 octahedra, corners with four TiSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, an edgeedge with one NaSe6 octahedra, an edgeedge with one TiSe4 tetrahedra, an edgeedge with one NaSe5 trigonal bipyramid, and faces with two equivalent NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. There are a spread of Na–Se bond distances ranging from 2.90–3.48 Å. In the second Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with four NaSe6 octahedra, corners with four TiSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, an edgeedge with one NaSe6 octahedra, an edgeedge with one TiSe4 tetrahedra, an edgeedge with one NaSe5 trigonal bipyramid, and faces with two equivalent NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 31–54°. There are a spread of Na–Se bond distances ranging from 2.98–3.43 Å. In the third Na1+ site, Na1+ is bonded to six Se2- atoms to form distorted NaSe6 octahedra that share corners with four NaSe6 octahedra, corners with two equivalent TiSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, an edgeedge with one NaSe6 octahedra, edges with two equivalent TiSe4 tetrahedra, and edges with three NaSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 31–48°. There are a spread of Na–Se bond distances ranging from 2.93–3.24 Å. In the fourth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Na–Se bond distances ranging from 2.89–3.39 Å. In the fifth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Na–Se bond distances ranging from 2.96–3.13 Å. In the sixth Na1+ site, Na1+ is bonded to five Se2- atoms to form distorted NaSe5 trigonal bipyramids that share corners with four NaSe6 octahedra, a cornercorner with one TiSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, edges with two NaSe6 octahedra, edges with two equivalent TiSe4 tetrahedra, and edges with three NaSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 36–54°. There are a spread of Na–Se bond distances ranging from 2.97–3.14 Å. In the seventh Na1+ site, Na1+ is bonded to five Se2- atoms to form NaSe5 trigonal bipyramids that share corners with two equivalent NaSe6 octahedra, corners with three TiSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, edges with three NaSe6 octahedra, an edgeedge with one TiSe4 tetrahedra, and edges with three NaSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 25–73°. There are a spread of Na–Se bond distances ranging from 2.88–3.18 Å. In the eighth Na1+ site, Na1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Na–Se bond distances ranging from 3.00–3.08 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to four Se2- atoms to form TiSe4 tetrahedra that share corners with six NaSe6 octahedra, corners with two equivalent NaSe5 trigonal bipyramids, and edges with three NaSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 29–62°. There are a spread of Ti–Se bond distances ranging from 2.39–2.43 Å. In the second Ti4+ site, Ti4+ is bonded to four Se2- atoms to form TiSe4 tetrahedra that share corners with four NaSe6 octahedra, corners with two NaSe5 trigonal bipyramids, and edges with four NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 38–68°. There are a spread of Ti–Se bond distances ranging from 2.38–2.44 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one Ti4+ atom. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one Ti4+ atom. In the third Se2- site, Se2- is bonded in a distorted pentagonal bipyramidal geometry to six Na1+ and one Ti4+ atom. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Na1+ and one Ti4+ atom. In the fifth Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one Ti4+ atom. In the sixth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Na1+ and one Ti4+ atom. In the seventh Se2- site, Se2- is bonded in a 6-coordinate geometry to five Na1+ and one Ti4+ atom. In the eighth Se2- site, Se2- is bonded in a 1-coordinate geometry to four Na1+ and one Ti4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na7In3Se8 by Materials Project

Na7In3Se8 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Se2- atoms to form distorted NaSe6 octahedra that share corners with seven NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, corners with five InSe4 tetrahedra, edges with six NaSe6 octahedra, edges with three InSe4 tetrahedra, and a faceface with one NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 18–52°. There are a spread of Na–Se bond distances ranging from 2.88–3.54 Å. In the second Na1+ site, Na1+ is bonded to six Se2- atoms to form distorted NaSe6 octahedra that share corners with seven NaSe6 octahedra, corners with two equivalent NaSe4 tetrahedra, corners with four InSe4 tetrahedra, edges with six NaSe6 octahedra, edges with three InSe4 tetrahedra, and a faceface with one NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 15–53°. There are a spread of Na–Se bond distances ranging from 2.88–3.65 Å. In the third Na1+ site, Na1+ is bonded to six Se2- atoms to form distorted NaSe6 octahedra that share corners with seven NaSe6 octahedra, corners with two equivalent NaSe4 tetrahedra, corners with four InSe4 tetrahedra, edges with six NaSe6 octahedra, an edgeedge with one NaSe4 tetrahedra, edges with two InSe4 tetrahedra, and a faceface with one NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 11–60°. There are a spread of Na–Se bond distances ranging from 2.93–3.61 Å. In the fourth Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with seven NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, corners with five InSe4 tetrahedra, edges with six NaSe6 octahedra, an edgeedge with one InSe4 tetrahedra, edges with two equivalent NaSe4 tetrahedra, and a faceface with one NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 10–60°. There are a spread of Na–Se bond distances ranging from 2.96–3.49 Å. In the fifth Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with ten NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, corners with three InSe4 tetrahedra, edges with two NaSe6 octahedra, an edgeedge with one NaSe4 tetrahedra, edges with three InSe4 tetrahedra, and faces with two NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 36–60°. There are a spread of Na–Se bond distances ranging from 2.89–3.27 Å. In the sixth Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with ten NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, corners with three InSe4 tetrahedra, edges with two NaSe6 octahedra, an edgeedge with one NaSe4 tetrahedra, edges with three InSe4 tetrahedra, and faces with two NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 34–60°. There are a spread of Na–Se bond distances ranging from 2.90–3.38 Å. In the seventh Na1+ site, Na1+ is bonded to four Se2- atoms to form NaSe4 tetrahedra that share corners with eight NaSe6 octahedra, corners with two InSe4 tetrahedra, edges with five NaSe6 octahedra, and an edgeedge with one InSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 22–77°. There are a spread of Na–Se bond distances ranging from 2.89–2.94 Å. There are three inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with eight NaSe6 octahedra, corners with two InSe4 tetrahedra, edges with five NaSe6 octahedra, and an edgeedge with one NaSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–66°. There are a spread of In–Se bond distances ranging from 2.56–2.70 Å. In the second In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with eight NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, a cornercorner with one InSe4 tetrahedra, edges with five NaSe6 octahedra, and an edgeedge with one InSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–68°. There are a spread of In–Se bond distances ranging from 2.58–2.68 Å. In the third In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with eight NaSe6 octahedra, a cornercorner with one NaSe4 tetrahedra, a cornercorner with one InSe4 tetrahedra, edges with five NaSe6 octahedra, and an edgeedge with one InSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–69°. There are a spread of In–Se bond distances ranging from 2.58–2.68 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four Na1+ and two equivalent In3+ atoms to form distorted SeNa4In2 pentagonal pyramids that share a cornercorner with one SeNa5In pentagonal pyramid and edges with three SeNa4In2 pentagonal pyramids. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one In3+ atom. In the third Se2- site, Se2- is bonded in a 7-coordinate geometry to five Na1+ and two In3+ atoms. In the fourth Se2- site, Se2- is bonded in a 7-coordinate geometry to five Na1+ and two In3+ atoms. In the fifth Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one In3+ atom. In the sixth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Na1+ and one In3+ atom. In the seventh Se2- site, Se2- is bonded to four Na1+ and two equivalent In3+ atoms to form distorted SeNa4In2 pentagonal pyramids that share a cornercorner with one SeNa5In pentagonal pyramid and edges with three SeNa4In2 pentagonal pyramids. In the eighth Se2- site, Se2- is bonded to five Na1+ and one In3+ atom to form a mixture of distorted edge and corner-sharing SeNa5In pentagonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Bi2(PSe3)3 by Materials Project

Bi2(PSe3)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Bi+1.50+ sites. In the first Bi+1.50+ site, Bi+1.50+ is bonded to seven Se2- atoms to form distorted edge-sharing BiSe7 pentagonal bipyramids. There are a spread of Bi–Se bond distances ranging from 2.94–3.32 Å. In the second Bi+1.50+ site, Bi+1.50+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Bi–Se bond distances ranging from 2.81–3.42 Å. In the third Bi+1.50+ site, Bi+1.50+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Bi–Se bond distances ranging from 2.79–3.37 Å. In the fourth Bi+1.50+ site, Bi+1.50+ is bonded to six Se2- atoms to form distorted edge-sharing BiSe6 pentagonal pyramids. There are a spread of Bi–Se bond distances ranging from 2.92–3.20 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.21 Å) and two longer (2.22 Å) P–Se bond lengths. In the second P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.20 Å) and two longer (2.22 Å) P–Se bond lengths. In the third P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.19–2.26 Å. In the fourth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.18–2.25 Å. In the fifth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are two shorter (2.22 Å) and one longer (2.25 Å) P–Se bond lengths. In the sixth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.21–2.26 Å. There are eighteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted L-shaped geometry to one Bi+1.50+ and one P5+ atom. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to two Bi+1.50+ and one P5+ atom. In the third Se2- site, Se2- is bonded in a 2-coordinate geometry to one Bi+1.50+ and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a distorted L-shaped geometry to one Bi+1.50+ and one P5+ atom. In the fifth Se2- site, Se2- is bonded in a distorted water-like geometry to one Bi+1.50+ and one P5+ atom. In the sixth Se2- site, Se2- is bonded in a 1-coordinate geometry to two Bi+1.50+ and one P5+ atom. In the seventh Se2- site, Se2- is bonded in a 1-coordinate geometry to two equivalent Bi+1.50+ and one P5+ atom. In the eighth Se2- site, Se2- is bonded in a distorted water-like geometry to one Bi+1.50+ and one P5+ atom. In the ninth Se2- site, Se2- is bonded in a distorted water-like geometry to one Bi+1.50+ and one P5+ atom. In the tenth Se2- site, Se2- is bonded in a distorted water-like geometry to one Bi+1.50+ and one P5+ atom. In the eleventh Se2- site, Se2- is bonded in a distorted L-shaped geometry to one Bi+1.50+ and one P5+ atom. In the twelfth Se2- site, Se2- is bonded in a distorted single-bond geometry to two Bi+1.50+ and one P5+ atom. In the thirteenth Se2- site, Se2- is bonded in a 1-coordinate geometry to two Bi+1.50+ and one P5+ atom. In the fourteenth Se2- site, Se2- is bonded in a 1-coordinate geometry to two Bi+1.50+ and one P5+ atom. In the fifteenth Se2- site, Se2- is bonded in a distorted water-like geometry to one Bi+1.50+ and one P5+ atom. In the sixteenth Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Bi+1.50+ and one P5+ atom. In the seventeenth Se2- site, Se2- is bonded in a distorted L-shaped geometry to one Bi+1.50+ and one P5+ atom. In the eighteenth Se2- site, Se2- is bonded in a 1-coordinate geometry to two Bi+1.50+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSe2 by Materials Project

LaSe2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. La3+ is bonded in a 9-coordinate geometry to nine Se+1.50- atoms. There are a spread of La–Se bond distances ranging from 3.03–3.32 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded in a 5-coordinate geometry to four equivalent La3+ and one Se+1.50- atom. The Se–Se bond length is 2.52 Å. In the second Se+1.50- site, Se+1.50- is bonded to five equivalent La3+ atoms to form a mixture of distorted edge and corner-sharing SeLa5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaB9Se8 by Materials Project

NaB9Se8 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Na–Se bond distances ranging from 3.13–3.65 Å. There are nine inequivalent B+1.67+ sites. In the first B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the second B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the third B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the fourth B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There are a spread of B–Se bond distances ranging from 1.93–2.01 Å. In the fifth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.03 Å. In the sixth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the seventh B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There is two shorter (1.96 Å) and one longer (1.97 Å) B–Se bond length. In the eighth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the ninth B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There are a spread of B–Se bond distances ranging from 1.95–1.98 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted L-shaped geometry to two equivalent Na1+ and two B+1.67+ atoms. In the second Se2- site, Se2- is bonded in an L-shaped geometry to two B+1.67+ atoms. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to one Na1+ and two B+1.67+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted single-bond geometry to one B+1.67+ atom. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the sixth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the seventh Se2- site, Se2- is bonded in a 3-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the eighth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Na1+ and two B+1.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs3Bi7Se12 by Materials Project

Cs3Bi7Se12 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.56–3.90 Å. In the second Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.63–3.92 Å. In the third Cs1+ site, Cs1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.63–3.90 Å. There are seven inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–6°. There are a spread of Bi–Se bond distances ranging from 2.85–3.15 Å. In the second Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–11°. There are a spread of Bi–Se bond distances ranging from 2.82–3.25 Å. In the third Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of Bi–Se bond distances ranging from 2.85–3.13 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–10°. There are a spread of Bi–Se bond distances ranging from 2.82–3.25 Å. In the fifth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of Bi–Se bond distances ranging from 2.90–3.09 Å. In the sixth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–6°. There are a spread of Bi–Se bond distances ranging from 2.84–3.15 Å. In the seventh Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of Bi–Se bond distances ranging from 2.92–3.02 Å. There are twelve inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form SeCs2Bi3 square pyramids that share a cornercorner with one SeBi6 octahedra, corners with six SeCsBi4 trigonal bipyramids, edges with four SeCs3Bi3 octahedra, edges with two equivalent SeCs2Bi3 square pyramids, and edges with two SeCsBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. In the second Se2- site, Se2- is bonded to six Bi3+ atoms to form SeBi6 octahedra that share corners with three SeCs2Bi3 square pyramids, edges with six SeBi6 octahedra, an edgeedge with one SeCs2Bi3 square pyramid, and edges with four SeCsBi4 trigonal bipyramids. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cs1+ and two equivalent Bi3+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cs1+ and two equivalent Bi3+ atoms. In the fifth Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form SeCs2Bi3 square pyramids that share corners with two equivalent SeBi6 octahedra, corners with seven SeCsBi4 trigonal bipyramids, edges with three SeBi6 octahedra, edges with two equivalent SeCs2Bi3 square pyramids, and an edgeedge with one SeCs2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 6°. In the sixth Se2- site, Se2- is bonded to three Cs1+ and three Bi3+ atoms to form distorted SeCs3Bi3 octahedra that share corners with two equivalent SeBi6 octahedra, corners with five SeCsBi4 trigonal bipyramids, edges with five SeBi6 octahedra, and edges with two equivalent SeCs2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the seventh Se2- site, Se2- is bonded to one Cs1+ and four Bi3+ atoms to form SeCsBi4 trigonal bipyramids that share corners with two equivalent SeCs3Bi3 octahedra, corners with three SeCs2Bi3 square pyramids, corners with three SeCsBi4 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, an edgeedge with one SeCs2Bi3 square pyramid, and edges with two equivalent SeCs2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 34°. In the eighth Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form distorted SeCs2Bi3 trigonal bipyramids that share a cornercorner with one SeBi6 octahedra, corners with four SeCs2Bi3 square pyramids, an edgeedge with one SeCs2Bi3 square pyramid, and edges with six SeCsBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 2°. In the ninth Se2- site, Se2- is bonded to one Cs1+ and four Bi3+ atoms to form SeCsBi4 trigonal bipyramids that share a cornercorner with one SeCs3Bi3 octahedra, corners with two equivalent SeCs2Bi3 square pyramids, corners with five SeCsBi4 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, and edges with three SeCs2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 9°. In the tenth Se2- site, Se2- is bonded in a 6-coordinate geometry to three Cs1+ and three Bi3+ atoms. In the eleventh Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form distorted SeCs2Bi3 trigonal bipyramids that share corners with three SeCs3Bi3 octahedra, corners with four SeCs2Bi3 square pyramids, corners with two equivalent SeCsBi4 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, an edgeedge with one SeCs2Bi3 square pyramid, and edges with three SeCsBi4 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 7–42°. In the twelfth Se2- site, Se2- is bonded to six Bi3+ atoms to form SeBi6 octahedra that share corners with two equivalent SeCs3Bi3 octahedra, corners with two SeCs2Bi3 trigonal bipyramids, edges with five SeBi6 octahedra, edges with four SeCs2Bi3 square pyramids, and edges with two equivalent SeCsBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba3Bi6PbSe13 by Materials Project

Ba3PbBi6Se13 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Ba–Se bond distances ranging from 3.32–3.55 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Ba–Se bond distances ranging from 3.32–3.55 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Ba–Se bond distances ranging from 3.32–3.65 Å. Pb2+ is bonded to six Se2- atoms to form PbSe6 octahedra that share corners with four BiSe6 octahedra, edges with two equivalent PbSe6 octahedra, and edges with four BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 5–59°. There are a spread of Pb–Se bond distances ranging from 3.07–3.14 Å. There are six inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share a cornercorner with one PbSe6 octahedra, corners with four BiSe6 octahedra, edges with two equivalent PbSe6 octahedra, and edges with eight BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 4–7°. There are a spread of Bi–Se bond distances ranging from 2.77–3.22 Å. In the second Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Bi–Se bond distances ranging from 2.78–3.21 Å. In the third Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with three equivalent PbSe6 octahedra and edges with six BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Bi–Se bond distances ranging from 2.92–3.04 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Bi–Se bond distances ranging from 2.75–3.50 Å. In the fifth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with two equivalent BiSe6 octahedra, edges with two equivalent PbSe6 octahedra, and edges with seven BiSe6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Bi–Se bond distances ranging from 2.76–3.31 Å. In the sixth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Bi–Se bond distances ranging from 2.84–3.12 Å. There are thirteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Ba2+ and two equivalent Bi3+ atoms. In the second Se2- site, Se2- is bonded to one Ba2+ and five Bi3+ atoms to form SeBaBi5 octahedra that share corners with two equivalent SeBi5Pb octahedra, corners with three SeBa2Bi3 trigonal bipyramids, edges with five SeBaBi5 octahedra, edges with four SeBa4Bi square pyramids, and edges with two equivalent SeBa2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°. In the third Se2- site, Se2- is bonded to two Ba2+ and three Bi3+ atoms to form distorted SeBa2Bi3 trigonal bipyramids that share corners with three SeBaBi5 octahedra, corners with five SeBa4Bi square pyramids, corners with three SeBa2Bi3 trigonal bipyramids, edges with three SeBaBi5 octahedra, and edges with two equivalent SeBa4Bi square pyramids. The corner-sharing octahedra tilt angles range from 8–43°. In the fourth Se2- site, Se2- is bonded to four Ba2+ and one Bi3+ atom to form distorted SeBa4Bi square pyramids that share corners with four SeBa2BiPb2 square pyramids, corners with five SeBa2Bi3 trigonal bipyramids, edges with two equivalent SeBaBi5 octahedra, edges with four SeBa4Bi square pyramids, and edges with three SeBa2Bi3 trigonal bipyramids. In the fifth Se2- site, Se2- is bonded to two equivalent Ba2+, two equivalent Pb2+, and one Bi3+ atom to form distorted SeBa2BiPb2 square pyramids that share a cornercorner with one SeBi5Pb octahedra, corners with two equivalent SeBa4Bi square pyramids, corners with four SeBa2Bi3 trigonal bipyramids, corners with two equivalent SeBi3Pb trigonal pyramids, edges with four SeBaBi5 octahedra, edges with three SeBa4Bi square pyramids, and an edgeedge with one SeBa2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 3°. In the sixth Se2- site, Se2- is bonded to two equivalent Ba2+ and three Bi3+ atoms to form distorted SeBa2Bi3 square pyramids that share corners with two equivalent SeBa4Bi square pyramids, corners with three SeBa2Bi3 trigonal bipyramids, corners with four equivalent SeBi3Pb trigonal pyramids, edges with two equivalent SeBaBi5 octahedra, edges with three SeBa2Bi3 square pyramids, edges with two equivalent SeBa2Bi3 trigonal bipyramids, and an edgeedge with one SeBi3Pb trigonal pyramid. In the seventh Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Ba2+, two equivalent Pb2+, and one Bi3+ atom. In the eighth Se2- site, Se2- is bonded to one Ba2+ and five Bi3+ atoms to form SeBaBi5 octahedra that share a cornercorner with one SeBa4Bi square pyramid, corners with five SeBa2Bi3 trigonal bipyramids, edges with four equivalent SeBaBi5 octahedra, edges with four SeBa2Bi3 square pyramids, and edges with four SeBa2Bi3 trigonal bipyramids. In the ninth Se2- site, Se2- is bonded to one Pb2+ and five Bi3+ atoms to form SeBi5Pb octahedra that share corners with two equivalent SeBaBi5 octahedra, a cornercorner with one SeBa2BiPb2 square pyramid, corners with two equivalent SeBa2Bi3 trigonal bipyramids, a cornercorner with one SeBi3Pb trigonal pyramid, edges with seven SeBaBi5 octahedra, edges with two equivalent SeBa2BiPb2 square pyramids, and an edgeedge with one SeBa2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 5°. In the tenth Se2- site, Se2- is bonded to four Ba2+ and one Bi3+ atom to form distorted SeBa4Bi square pyramids that share a cornercorner with one SeBaBi5 octahedra, corners with four SeBa4Bi square pyramids, edges with two equivalent SeBaBi5 octahedra, edges with four SeBa4Bi square pyramids, and edges with four SeBa2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. In the eleventh Se2- site, Se2- is bonded to two Ba2+ and three Bi3+ atoms to form distorted SeBa2Bi3 trigonal bipyramids that share corners with three SeBaBi5 octahedra, corners with three SeBa2BiPb2 square pyramids, corners with three SeBa2Bi3 trigonal bipyramids, edges with three equivalent SeBaBi5 octahedra, edges with four SeBa4Bi square pyramids, and edges with two equivalent SeBa2Bi3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 9–43°. In the twelfth Se2- site, Se2- is bonded to two equivalent Ba2+ and three Bi3+ atoms to form distorted SeBa2Bi3 trigonal bipyramids that share corners with four SeBaBi5 octahedra, corners with four SeBa4Bi square pyramids, corners with three equivalent SeBi3Pb trigonal pyramids, an edgeedge with one SeBaBi5 octahedra, edges with four SeBa4Bi square pyramids, and edges with four SeBa2Bi3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 3–44°. In the thirteenth Se2- site, Se2- is bonded to one Pb2+ and three equivalent Bi3+ atoms to form distorted SeBi3Pb trigonal pyramids that share a cornercorner with one SeBi5Pb octahedra, corners with six SeBa2BiPb2 square pyramids, corners with three equivalent SeBa2Bi3 trigonal bipyramids, corners with two equivalent SeBi3Pb trigonal pyramids, an edgeedge with one SeBa2Bi3 square pyramid, and edges with two equivalent SeBi3Pb trigonal pyramids. The corner-sharing octahedral tilt angles are 2°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl3In7Se10 by Materials Project

Tl3In7Se10 is I4/mcm-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.49–3.51 Å. In the second Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to eight Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.49–3.52 Å. In the third Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to eight Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.49–3.53 Å. There are seven inequivalent In+2.43+ sites. In the first In+2.43+ site, In+2.43+ is bonded to four Se2- atoms to form edge-sharing InSe4 tetrahedra. There are one shorter (2.65 Å) and three longer (2.66 Å) In–Se bond lengths. In the second In+2.43+ site, In+2.43+ is bonded to four Se2- atoms to form edge-sharing InSe4 tetrahedra. There are a spread of In–Se bond distances ranging from 2.65–2.67 Å. In the third In+2.43+ site, In+2.43+ is bonded to four Se2- atoms to form edge-sharing InSe4 tetrahedra. There are three shorter (2.65 Å) and one longer (2.66 Å) In–Se bond lengths. In the fourth In+2.43+ site, In+2.43+ is bonded to four Se2- atoms to form edge-sharing InSe4 tetrahedra. There are three shorter (2.65 Å) and one longer (2.66 Å) In–Se bond lengths. In the fifth In+2.43+ site, In+2.43+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of In–Se bond distances ranging from 3.49–3.51 Å. In the sixth In+2.43+ site, In+2.43+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are two shorter (3.49 Å) and six longer (3.50 Å) In–Se bond lengths. In the seventh In+2.43+ site, In+2.43+ is bonded to four Se2- atoms to form edge-sharing InSe4 tetrahedra. There are two shorter (2.65 Å) and two longer (2.66 Å) In–Se bond lengths. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 2-coordinate geometry to two Tl1+ and four In+2.43+ atoms. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to three equivalent Tl1+ and three In+2.43+ atoms. In the third Se2- site, Se2- is bonded in a 2-coordinate geometry to two Tl1+ and four In+2.43+ atoms. In the fourth Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Tl1+ and four In+2.43+ atoms. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to two Tl1+ and four In+2.43+ atoms. In the sixth Se2- site, Se2- is bonded in a 2-coordinate geometry to three equivalent Tl1+ and three In+2.43+ atoms. In the seventh Se2- site, Se2- is bonded in a 2-coordinate geometry to two Tl1+ and four In+2.43+ atoms. In the eighth Se2- site, Se2- is bonded in a 2-coordinate geometry to three Tl1+ and three In+2.43+ atoms. In the ninth Se2- site, Se2- is bonded in a 2-coordinate geometry to three Tl1+ and three In+2.43+ atoms. In the tenth Se2- site, Se2- is bonded in a 2-coordinate geometry to two Tl1+ and four In+2.43+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ga7(CuSe4)3 by Materials Project

Ga7(CuSe4)3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with three CuSe4 tetrahedra and corners with nine GaSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.40–2.44 Å. In the second Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with four CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.38–2.47 Å. In the third Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with five CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.37–2.43 Å. There are seven inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with two equivalent CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.43–2.51 Å. In the second Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with four CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.42–2.51 Å. In the third Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with two equivalent CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.35–2.53 Å. In the fourth Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share a cornercorner with one CuSe4 tetrahedra and corners with seven GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.33–2.52 Å. In the fifth Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with three CuSe4 tetrahedra and corners with five GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.39–2.53 Å. In the sixth Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with four GaSe4 tetrahedra and corners with six CuSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.42–2.51 Å. In the seventh Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with five CuSe4 tetrahedra and corners with five GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.37–2.58 Å. There are twelve inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the second Se2- site, Se2- is bonded in a water-like geometry to two Ga3+ atoms. In the third Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fourth Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fifth Se2- site, Se2- is bonded to one Cu1+ and three Ga3+ atoms to form corner-sharing SeGa3Cu tetrahedra. In the sixth Se2- site, Se2- is bonded in a water-like geometry to two Ga3+ atoms. In the seventh Se2- site, Se2- is bonded to two Cu1+ and two equivalent Ga3+ atoms to form corner-sharing SeGa2Cu2 tetrahedra. In the eighth Se2- site, Se2- is bonded to one Cu1+ and three Ga3+ atoms to form corner-sharing SeGa3Cu tetrahedra. In the ninth Se2- site, Se2- is bonded to two equivalent Cu1+ and two Ga3+ atoms to form corner-sharing SeGa2Cu2 tetrahedra. In the tenth Se2- site, Se2- is bonded to two equivalent Cu1+ and two Ga3+ atoms to form corner-sharing SeGa2Cu2 tetrahedra. In the eleventh Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to one Cu1+ and two equivalent Ga3+ atoms. In the twelfth Se2- site, Se2- is bonded to three Cu1+ and one Ga3+ atom to form corner-sharing SeGaCu3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Pb17Se20 by Materials Project

Pr2Pb17Se20 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Pr3+ is bonded to six Se2- atoms to form PrSe6 octahedra that share corners with six PbSe6 octahedra, edges with two equivalent PrSe6 octahedra, and edges with eight PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 3–7°. There are a spread of Pr–Se bond distances ranging from 2.93–3.09 Å. There are nine inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to six Se2- atoms to form PbSe6 octahedra that share corners with two equivalent PbSe6 octahedra, corners with three equivalent PrSe6 octahedra, edges with three equivalent PrSe6 octahedra, and edges with seven PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 5–7°. There are a spread of Pb–Se bond distances ranging from 3.05–3.20 Å. In the second Pb2+ site, Pb2+ is bonded to six Se2- atoms to form PbSe6 octahedra that share corners with six PbSe6 octahedra, edges with two equivalent PrSe6 octahedra, and edges with ten PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Pb–Se bond distances ranging from 3.02–3.17 Å. In the third Pb2+ site, Pb2+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are a spread of Pb–Se bond distances ranging from 3.00–3.21 Å. In the fourth Pb2+ site, Pb2+ is bonded to six Se2- atoms to form PbSe6 octahedra that share a cornercorner with one PrSe6 octahedra, corners with three PbSe6 octahedra, edges with two equivalent PrSe6 octahedra, and edges with nine PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. There are a spread of Pb–Se bond distances ranging from 2.93–3.31 Å. In the fifth Pb2+ site, Pb2+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Pb–Se bond distances ranging from 3.04–3.19 Å. In the sixth Pb2+ site, Pb2+ is bonded to six Se2- atoms to form PbSe6 octahedra that share corners with two equivalent PrSe6 octahedra, corners with four PbSe6 octahedra, an edgeedge with one PrSe6 octahedra, and edges with eleven PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Pb–Se bond distances ranging from 3.03–3.27 Å. In the seventh Pb2+ site, Pb2+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing PbSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are two shorter (3.09 Å) and four longer (3.12 Å) Pb–Se bond lengths. In the eighth Pb2+ site, Pb2+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Pb–Se bond distances ranging from 3.07–3.13 Å. In the ninth Pb2+ site, Pb2+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing PbSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Pb–Se bond distances ranging from 3.04–3.18 Å. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Pr3+ and three Pb2+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Pr3+ and three equivalent Pb2+ atoms to form distorted SePr2Pb3 square pyramids that share corners with four SePrPb5 octahedra, edges with four SePrPb5 octahedra, and edges with four equivalent SePr2Pb3 square pyramids. The corner-sharing octahedral tilt angles are 6°. In the third Se2- site, Se2- is bonded to one Pr3+ and five Pb2+ atoms to form distorted SePrPb5 octahedra that share corners with three SePr2Pb4 octahedra, corners with two equivalent SePr2Pb3 square pyramids, edges with seven SePrPb5 octahedra, and edges with three equivalent SePr2Pb3 square pyramids. The corner-sharing octahedra tilt angles range from 3–5°. In the fourth Se2- site, Se2- is bonded to six Pb2+ atoms to form SePb6 octahedra that share corners with four SePb6 octahedra and edges with eleven SePrPb5 octahedra. The corner-sharing octahedra tilt angles range from 1–4°. In the fifth Se2- site, Se2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing SePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the sixth Se2- site, Se2- is bonded to two equivalent Pr3+ and four Pb2+ atoms to form distorted SePr2Pb4 octahedra that share corners with four SePrPb5 octahedra, corners with two equivalent SePr2Pb3 square pyramids, edges with nine SePrPb5 octahedra, and an edgeedge with one SePr2Pb3 square pyramid. The corner-sharing octahedra tilt angles range from 1–4°. In the seventh Se2- site, Se2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing SePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the eighth Se2- site, Se2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing SePb6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the ninth Se2- site, Se2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing SePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the tenth Se2- site, Se2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing SePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°.

36 MATERIALS SCIENCE↗