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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Effect of layer bending on montmorillonite hydration and structure from molecular simulation

Conceptual models of smectite hydration include planar (flat) clay layers that undergo stepwise expansion as successive monolayers of water molecules fill the interlayer regions. However, X-ray diffraction (XRD) studies indicate the presence of interstratified hydration states, suggesting non-uniform interlayer hydration in smectites. Additionally, recent theoretical studies have shown that clay layers can adopt bent configurations over nanometer-scale lateral dimensions with minimal effect on mechanical properties. Therefore, in this study we used molecular simulations to evaluate structural properties and water adsorption isotherms for montmorillonite models composed of bent clay layers in mixed hydration states. Results are compared with models consisting of planar clay layers with interstratified hydration states (e.g. 1W–2W). The small degree of bending in these models (up to 1.5 Å of vertical displacement over a 1.3 nm lateral dimension) had little or no effect on bond lengths and angle distributions within the clay layers. Except for models that included dry states, porosities and simulated water adsorption isotherms were nearly identical for bent or flat clay layers with the same averaged layer spacing. Similar agreement was seen with Na- and Ca-exchanged clays. In conclusion, while the small bent models did not retain their configurations during unconstrained molecular dynamics simulation with flexible clay layers, we show that bent structures are stable at much larger length scales by simulating a 41.6×7.1 nm 2 system that included dehydrated and hydrated regions in the same interlayer.

58 GEOSCIENCES↗
DOE OSTI2023

MD Simulation of Water Using a Rigid Body Description Requires a Small Time Step to Ensure Equipartition

In simulations of aqueous systems, it is common to freeze the bond vibration and angle bending modes in water to allow for a longer time step δt for integrating the equations of motion. Thus, δt = 2 fs is often used in simulating rigid models of water. We simulate the SPC/E model of water using δt from 0.5 to 3.0 fs and up to 4 fs using hydrogen mass repartitioning. In these simulations, we find that for all but δt = 0.5 fs, equipartition is not obtained between translational and rotational modes, with the rotational modes exhibiting a lower temperature than the translation modes. To probe the reasons for the lack of equipartition, we study the autocorrelation of the translational velocity of the center of mass and the angular velocity of the rigid water molecule, respectively. Here, we find that the rotational relaxation occurs on a timescale comparable to vibrational periods, calling into question the original motivations for freezing the vibrations. Furthermore, a time step with δt ≥ 1 fs is not able to capture accurately the fast rotational relaxation, which reveals its impact as an effective slowing-down of rotational relaxation. The fluctuation–dissipation relation then leads to the conclusion that the rotational temperature should be cooler for δt greater than the reference value of 0.5 fs. Consideration of fluctuation–dissipation in equilibrium molecular dynamics simulations also emphasizes the need to capture the temporal evolution of fluctuations with fidelity and the role of δt in this regard. The time step also influences the solution thermodynamic properties: both the mean system potential energies and the excess entropy of hydration of a soft repulsive cavity are sensitive to δt.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Molecular structure retrieval directly from laboratory-frame photoelectron spectra in laser-induced electron diffraction

Ubiquitous to most molecular scattering methods is the challenge to retrieve bond distance and angle from the scattering signals since this requires convergence of pattern matching algorithms or fitting methods. This problem is typically exacerbated when imaging larger molecules or for dynamic systems with little a priori knowledge. Here, we employ laser-induced electron diffraction (LIED) which is a powerful means to determine the precise atomic configuration of an isolated gas-phase molecule with picometre spatial and attosecond temporal precision. We introduce a simple molecular retrieval method, which is based only on the identification of critical points in the oscillating molecular interference scattering signal that is extracted directly from the laboratory-frame photoelectron spectrum. The method is compared with a Fourier-based retrieval method, and we show that both methods correctly retrieve the asymmetrically stretched and bent field-dressed configuration of the asymmetric top molecule carbonyl sulfide (OCS), which is confirmed by our quantum-classical calculations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Local lattice distortions and electronic phases in perovskite manganite Pr 0.5 Sr 0.5 MnO 3

We use variable temperature and magnetic field total x-ray scattering to study the crystal structure of the strongly correlated Pr 0.5 Sr 0.5 MnO 3 perovskite, which is a paramagnetic insulator at room temperature, becomes a ferromagnetic metal at 272 K and, upon further decreasing the temperature, turns into an antiferromagnetic insulator at 105 K. We find that a model featuring a monoclinic symmetry captures the structure and its temperature and field evolution well, eliminating the need to evoke a phase segregation scenario as done in prior studies. It appears that coupled variations in Mn–oxygen bonding distances and angles from their values in an undistorted perovskite lattice, i.e., coupled local lattice distortions, assist the phase transitions in Pr 0.5 Sr 0.5 MnO 3 , contributing to its unique physical properties. Local structural distortions thus emerge as an important degree of freedom in strongly correlated systems, in particular perovskite manganates, and, therefore, they should be fully accounted for when their fascinating physics is considered.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Multilevel atomic structural model for interstratified opal materials

The structure of opal has long fascinated scientists. It occurs in a number of structural states, ranging from amorphous to exhibiting features of stacking disorder. Opal-CT, where C and T signify cristobalite- and tridymite-like interstratification, represents an important link in the length scales between amorphous and crystalline states. However, details about local atomic (dis)order and arrangements extending to long-range stacking faults in opal polymorphs remain incompletely understood. Here, a multilevel modeling approach is reported that considers stacking states in correlation with the abundance of C and T segments as a high-level structural parameter (i.e. not each atom). Optimization accounting for inter-tetrahedral bond lengths and angles and the regularity of the silicate tetrahedra is included as lower levels of structural parameters. Together, a set of parameters with both coarse-grained and atomistic features for different levels of structural details is refined. Structural disorder at the ~10–100 Å distance scale is evaluated using experimental pair distribution function and diffraction datasets, comparing peak intensities, widths and asymmetry. Here this work presents a complete multilevel structural description of natural opal-CT and explains many of the unusual features observed in X-ray powder diffraction patterns. This modeling approach can be adopted generally for analyzing layered materials and their assembly into 3D structures.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Arginine off-kilter: guanidinium is not as planar as restraints denote

Crystallographic refinement of macromolecular structures relies on stereochemical restraints to mitigate the typically poor data-to-parameter ratio. For proteins, each amino acid has a unique set of geometry restraints which represent stereochemical information such as bond lengths, valence angles, torsion angles, dihedrals and planes. It has been shown that the geometry in refined structures can differ significantly from that present in libraries; for example, it was recently reported that the guanidinium moiety in arginine is not symmetric. In this work, the asymmetry of the N ∊ —C ζ —N η1 and N ∊ —C ζ —N η2 valence angles in the guanidinium moiety is confirmed. In addition, it was found that the C δ atom can deviate significantly (more than 20°) from the guanidinium plane. This requires the relaxation of the planar restraint for the C δ atom, as it otherwise causes the other atoms in the group to compensate by distorting the guanidinium core plane. A new set of restraints for the arginine side chain have therefore been formulated, and are available in the software package Phenix , that take into account the asymmetry of the group and the planar deviation of the C δ atom. This is an example of the need to regularly revisit the geometric restraint libraries used in macromolecular refinement so that they reflect the best knowledge of the structural chemistry of their components available at the time.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Analysis of Bis(trifluoromethylsulfonyl)imide Interactions with Metal Cations Through a Chemical Informatics Approach

Nominally weakly coordinating anions are useful for modulating the solubility and chemical properties of metal complexes, but identification and analysis of the systematics of the interactions of anions with cationic metal complexes has not received the attention it deserves. Here, a chemical informatics approach is demonstrated for identifying and quantitatively analyzing the ways that the bis(trifluoromethylsulfonyl)imide anion (TFSI) can interact with metal-containing species. An open access computer program (PyCIFTer) was developed to facilitate large-scale structural analysis of TFSI-containing species by utilization of experimental atomic coordinate data from single-crystal X-ray diffraction (XRD) studies obtained from the Cambridge Structural Database (CSD). PyCIFTer establishes a three-dimensional vector space from the raw atomic coordinates, generating acyclic, undirected graphs that are used to rapidly analyze the structural properties (bond lengths and angles) of TFSI in individual structures in sequential/batch fashion. The structures are sorted by PyCIFTer into groups based on pre-set and chemically sensible criteria, affording a comprehensive and systematic view of TFSI structural chemistry. This approach avoids tedious one-at-a-time interrogation of structures, a prospect unreasonable in this case, and many others of contemporary chemical relevance; there were over 1500 structures in the CSD containing TFSI as of November 2024. The results demonstrate that TFSI only rarely binds to cations in the solid state, favoring the formation of species in which TFSI is found in cations’ outer coordination spheres. The prospect of applying PyCIFTer to other moieties is also discussed. PyCIFTer is also schematically compared to the commercial CSD Python application programming interface (API). Taken together, this work demonstrates the usefulness of modular workflows for sequential/batch analysis of structural data from XRD, an approach that appears poised to accelerate the translation of legacy structural results into new chemical insights and hypotheses.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on Mn9Al8Fe3(SiO4)12 by Materials Project

Mn9Fe3Al8(SiO4)12 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are six inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mn–O bond distances ranging from 2.27–2.44 Å. In the second Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mn–O bond distances ranging from 2.27–2.44 Å. In the third Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mn–O bond distances ranging from 2.27–2.44 Å. In the fourth Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mn–O bond distances ranging from 2.27–2.44 Å. In the fifth Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.27 Å) and four longer (2.43 Å) Mn–O bond lengths. In the sixth Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.27 Å) and four longer (2.43 Å) Mn–O bond lengths. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.25 Å) and four longer (2.42 Å) Fe–O bond lengths. In the second Fe2+ site, Fe2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.25 Å) and four longer (2.42 Å) Fe–O bond lengths. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There is four shorter (1.91 Å) and two longer (1.92 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There is three shorter (1.91 Å) and three longer (1.92 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There is three shorter (1.91 Å) and three longer (1.92 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There is four shorter (1.91 Å) and two longer (1.92 Å) Al–O bond length. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–48°. All Si–O bond lengths are 1.66 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Si–O bond lengths are 1.66 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Fe2+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn2+, one Fe2+, one Al3+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Fe2+, one Al3+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Mn2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y3Ga(FeO3)4 by Materials Project

Y3Fe4GaO12 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are three inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.37–2.45 Å. In the second Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.37–2.47 Å. In the third Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.37–2.47 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent GaO4 tetrahedra and corners with four FeO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.04–2.06 Å. In the second Fe3+ site, Fe3+ is bonded to four equivalent O2- atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Fe–O bond lengths are 1.90 Å. In the third Fe3+ site, Fe3+ is bonded to four O2- atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Fe–O bond lengths are 1.90 Å. In the fourth Fe3+ site, Fe3+ is bonded to four equivalent O2- atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. All Fe–O bond lengths are 1.90 Å. Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with four equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 54°. All Ga–O bond lengths are 1.87 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to two Y3+ and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OY2Fe2 tetrahedra. In the second O2- site, O2- is bonded to two Y3+ and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OY2Fe2 tetrahedra. In the third O2- site, O2- is bonded to two Y3+ and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OY2Fe2 tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+, one Fe3+, and one Ga3+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+, one Fe3+, and one Ga3+ atom. In the sixth O2- site, O2- is bonded to two Y3+ and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OY2Fe2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U5P4S by Materials Project

U5P4S is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are three inequivalent U sites. In the first U site, U is bonded to six P atoms to form a mixture of corner and edge-sharing UP6 octahedra. The corner-sharing octahedral tilt angles are 0°. All U–P bond lengths are 2.77 Å. In the second U site, U is bonded to six equivalent P atoms to form a mixture of corner and edge-sharing UP6 octahedra. The corner-sharing octahedral tilt angles are 0°. All U–P bond lengths are 2.77 Å. In the third U site, U is bonded to three equivalent P and three equivalent S atoms to form a mixture of corner and edge-sharing UP3S3 octahedra. The corner-sharing octahedral tilt angles are 0°. All U–P bond lengths are 2.76 Å. All U–S bond lengths are 2.76 Å. There are two inequivalent P sites. In the first P site, P is bonded to six U atoms to form PU6 octahedra that share corners with three equivalent PU6 octahedra, corners with three equivalent SU6 octahedra, edges with three equivalent SU6 octahedra, and edges with nine PU6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second P site, P is bonded to six U atoms to form a mixture of corner and edge-sharing PU6 octahedra. The corner-sharing octahedral tilt angles are 0°. S is bonded to six equivalent U atoms to form SU6 octahedra that share corners with six equivalent PU6 octahedra, edges with six equivalent PU6 octahedra, and edges with six equivalent SU6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbGd2Ga5O12 by Materials Project

TbGd2Ga5O12 crystallizes in the tetragonal I4_122 space group. The structure is three-dimensional. Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.47 Å) Tb–O bond lengths. There are three inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.48 Å) Gd–O bond lengths. In the second Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.48 Å) Gd–O bond lengths. In the third Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.48 Å) Gd–O bond lengths. There are four inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six O2- atoms to form corner-sharing GaO6 octahedra. There are four shorter (2.02 Å) and two longer (2.03 Å) Ga–O bond lengths. In the second Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. In the third Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. In the fourth Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, one Gd3+, and two Ga3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Tb3+ and two Ga3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, one Gd3+, and two Ga3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Gd3+ and two Ga3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and two Ga3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Gd3+ and two Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2GdGa5O12 by Materials Project

Tb2GdGa5O12 crystallizes in the tetragonal I4_122 space group. The structure is three-dimensional. there are three inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.47 Å) Tb–O bond lengths. In the second Tb3+ site, Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.47 Å) Tb–O bond lengths. In the third Tb3+ site, Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.47 Å) Tb–O bond lengths. Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.48 Å) Gd–O bond lengths. There are four inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six O2- atoms to form corner-sharing GaO6 octahedra. There are five shorter (2.02 Å) and one longer (2.03 Å) Ga–O bond lengths. In the second Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. In the third Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. In the fourth Ga3+ site, Ga3+ is bonded to four O2- atoms to form corner-sharing GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. All Ga–O bond lengths are 1.87 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, one Gd3+, and two Ga3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and two Ga3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, one Gd3+, and two Ga3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Tb3+ and two Ga3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Tb3+ and two Ga3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Tb3+ and two Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgO by Materials Project

MgO is Molybdenum Carbide MAX Phase-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing MgO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 2°. All Mg–O bond lengths are 2.17 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.12 Å. In the fourth Mg2+ site, Mg2+ is bonded to six equivalent O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. All Mg–O bond lengths are 2.12 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to six equivalent Mg2+ atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner, edge, and face-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. In the fourth O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner, edge, and face-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgO by Materials Project

MgO is Molybdenum Carbide MAX Phase-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.12 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six equivalent O2- atoms to form a mixture of distorted edge and corner-sharing MgO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 2°. All Mg–O bond lengths are 2.17 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to six equivalent Mg2+ atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of face, edge, and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. In the third O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te7(OF5)6 by Materials Project

Te7(OF5)6 is Protactinium structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one Te7(OF5)6 cluster. there are three inequivalent Te6+ sites. In the first Te6+ site, Te6+ is bonded to six O2- atoms to form corner-sharing TeO6 octahedra. The corner-sharing octahedral tilt angles are 42°. All Te–O bond lengths are 1.96 Å. In the second Te6+ site, Te6+ is bonded to one O2- and five F1- atoms to form corner-sharing TeOF5 octahedra. The corner-sharing octahedral tilt angles are 42°. The Te–O bond length is 1.94 Å. All Te–F bond lengths are 1.87 Å. In the third Te6+ site, Te6+ is bonded to one O2- and five F1- atoms to form corner-sharing TeOF5 octahedra. The corner-sharing octahedral tilt angles are 42°. The Te–O bond length is 1.94 Å. There is one shorter (1.86 Å) and four longer (1.87 Å) Te–F bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te6+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te6+ atoms. The O–Te bond length is 1.94 Å. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Te6+ atoms. There are fifteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. The F–Te bond length is 1.87 Å. In the seventh F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. The F–Te bond length is 1.87 Å. In the eighth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. The F–Te bond length is 1.87 Å. In the ninth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. The F–Te bond length is 1.87 Å. In the tenth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. The F–Te bond length is 1.86 Å. In the eleventh F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the twelfth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the thirteenth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the fourteenth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the fifteenth F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta36B4C35 by Materials Project

Ta26C25Ta9C8TaBC(B)2BC1 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of two boron molecules; one BC1 sheet oriented in the (0, 0, 1) direction; one Ta26C25 sheet oriented in the (0, 0, 1) direction; one Ta9C8 sheet oriented in the (0, 0, 1) direction; and one TaBC sheet oriented in the (0, 0, 1) direction. In the BC1 sheet, B3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. All B–C bond lengths are 1.83 Å. C4- is bonded in a distorted trigonal planar geometry to three equivalent B3+ atoms. In the Ta26C25 sheet, there are eighteen inequivalent Ta+3.56+ sites. In the first Ta+3.56+ site, Ta+3.56+ is bonded in a 3-coordinate geometry to three equivalent C4- atoms. There are one shorter (2.14 Å) and two longer (2.15 Å) Ta–C bond lengths. In the second Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Ta–C bond lengths are 2.23 Å. In the third Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are five shorter (2.25 Å) and one longer (2.26 Å) Ta–C bond lengths. In the fourth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. All Ta–C bond lengths are 2.25 Å. In the fifth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.24 Å) and three longer (2.26 Å) Ta–C bond lengths. In the sixth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.24 Å) and three longer (2.25 Å) Ta–C bond lengths. In the seventh Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the eighth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the ninth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the tenth Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the eleventh Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the twelfth Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the thirteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the fourteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the fifteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the sixteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the seventeenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.23 Å) and two longer (2.24 Å) Ta–C bond lengths. In the eighteenth Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Ta–C bond lengths are 2.25 Å. There are fifteen inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the fifth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the sixth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the ninth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the tenth C4- site, C4- is bonded to six equivalent Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) C–Ta bond lengths. In the eleventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the twelfth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the thirteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.25 Å. In the Ta9C8 sheet, there are nine inequivalent Ta+3.56+ sites. In the first Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are five shorter (2.24 Å) and one longer (2.25 Å) Ta–C bond lengths. In the second Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ta–C bond distances ranging from 2.23–2.26 Å. In the third Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Ta–C bond lengths are 2.26 Å. In the fourth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. In the sixth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the seventh Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.23 Å) and four longer (2.24 Å) Ta–C bond lengths. In the eighth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.24 Å) and two longer (2.25 Å) Ta–C bond lengths. In the ninth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. There are eight inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.24 Å. In the fourth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.24 Å. In the fifth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the eighth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the TaBC sheet, Ta+3.56+ is bonded in a single-bond geometry to one C4- atom. The Ta–C bond length is 2.08 Å. B3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. There are a spread of B–C bond distances ranging from 1.81–1.85 Å. C4- is bonded to one Ta+3.56+ and three equivalent B3+ atoms to form corner-sharing CTaB3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cr8Fe2CuNiS16 by Materials Project

Cr8Fe2NiCuS16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent FeS4 tetrahedra, corners with three equivalent CuS4 tetrahedra, and edges with six CrS6 octahedra. There are three shorter (2.36 Å) and three longer (2.41 Å) Cr–S bond lengths. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent FeS4 tetrahedra, corners with three equivalent NiS4 tetrahedra, and edges with six CrS6 octahedra. There are three shorter (2.36 Å) and three longer (2.42 Å) Cr–S bond lengths. In the third Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one CuS4 tetrahedra, corners with two equivalent NiS4 tetrahedra, corners with three FeS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.35–2.42 Å. In the fourth Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one NiS4 tetrahedra, corners with two equivalent CuS4 tetrahedra, corners with three FeS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.35–2.42 Å. There are two inequivalent Fe+2.50+ sites. In the first Fe+2.50+ site, Fe+2.50+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Fe–S bond lengths are 2.16 Å. In the second Fe+2.50+ site, Fe+2.50+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Fe–S bond lengths are 2.16 Å. Ni2+ is bonded to four S2- atoms to form NiS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. All Ni–S bond lengths are 2.19 Å. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. All Cu–S bond lengths are 2.24 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Cu1+ atom. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Ni2+ atom. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Cu1+ atom. In the fourth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Ni2+ atom. In the fifth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Fe+2.50+ atom. In the sixth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Fe+2.50+ atom. In the seventh S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Fe+2.50+ atom. In the eighth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Fe+2.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn3Cr8FeS16 by Materials Project

Cr8FeZn3S16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent FeS4 tetrahedra, corners with three equivalent ZnS4 tetrahedra, and edges with six CrS6 octahedra. All Cr–S bond lengths are 2.41 Å. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with six ZnS4 tetrahedra and edges with six CrS6 octahedra. There are three shorter (2.40 Å) and three longer (2.41 Å) Cr–S bond lengths. In the third Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with two equivalent FeS4 tetrahedra, corners with four ZnS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.40–2.42 Å. In the fourth Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one FeS4 tetrahedra, corners with five ZnS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.40–2.42 Å. Fe2+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 57°. All Fe–S bond lengths are 2.31 Å. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four S2- atoms to form ZnS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Zn–S bond lengths are 2.35 Å. In the second Zn2+ site, Zn2+ is bonded to four S2- atoms to form ZnS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 58–59°. All Zn–S bond lengths are 2.35 Å. In the third Zn2+ site, Zn2+ is bonded to four S2- atoms to form ZnS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 58–59°. All Zn–S bond lengths are 2.35 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Cr3+ and one Zn2+ atom to form distorted corner-sharing SZnCr3 trigonal pyramids. In the second S2- site, S2- is bonded to three equivalent Cr3+ and one Fe2+ atom to form a mixture of distorted edge and corner-sharing SCr3Fe trigonal pyramids. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Fe2+ atom. In the fourth S2- site, S2- is bonded to three Cr3+ and one Zn2+ atom to form distorted SZnCr3 trigonal pyramids that share corners with twelve SZnCr3 trigonal pyramids and edges with three SCr3Fe trigonal pyramids. In the fifth S2- site, S2- is bonded to three equivalent Cr3+ and one Zn2+ atom to form a mixture of distorted edge and corner-sharing SZnCr3 trigonal pyramids. In the sixth S2- site, S2- is bonded to three equivalent Cr3+ and one Zn2+ atom to form distorted SZnCr3 trigonal pyramids that share corners with twelve SCr3Fe trigonal pyramids and edges with three equivalent SZnCr3 trigonal pyramids. In the seventh S2- site, S2- is bonded to three Cr3+ and one Zn2+ atom to form a mixture of distorted edge and corner-sharing SZnCr3 trigonal pyramids. In the eighth S2- site, S2- is bonded to three Cr3+ and one Zn2+ atom to form distorted SZnCr3 trigonal pyramids that share corners with nine SCr3Fe trigonal pyramids and edges with three SZnCr3 trigonal pyramids.

36 MATERIALS SCIENCE↗