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At least 1,207 records · Page 67
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DOE OSTI2020

Materials Data on TiGeRh by Materials Project

TiRhGe crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. there are three inequivalent Ti sites. In the first Ti site, Ti is bonded in a 5-coordinate geometry to two equivalent Rh and five Ge atoms. Both Ti–Rh bond lengths are 2.87 Å. There are two shorter (2.67 Å) and three longer (2.68 Å) Ti–Ge bond lengths. In the second Ti site, Ti is bonded in a 9-coordinate geometry to four Rh and five Ge atoms. There are two shorter (2.81 Å) and two longer (2.86 Å) Ti–Rh bond lengths. There are a spread of Ti–Ge bond distances ranging from 2.67–2.80 Å. In the third Ti site, Ti is bonded in a 11-coordinate geometry to six Rh and five Ge atoms. There are a spread of Ti–Rh bond distances ranging from 2.77–2.90 Å. There are a spread of Ti–Ge bond distances ranging from 2.69–2.96 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 8-coordinate geometry to four Ti and four Ge atoms. There are two shorter (2.52 Å) and two longer (2.53 Å) Rh–Ge bond lengths. In the second Rh site, Rh is bonded in a 8-coordinate geometry to four Ti and four Ge atoms. There are a spread of Rh–Ge bond distances ranging from 2.51–2.53 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to three Ti and six Rh atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Ti and three Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YGeRh2 by Materials Project

YRh2Ge crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Y sites. In the first Y site, Y is bonded in a 9-coordinate geometry to one Y, nine equivalent Rh, and three equivalent Ge atoms. The Y–Y bond length is 3.32 Å. There are three shorter (3.05 Å) and six longer (3.14 Å) Y–Rh bond lengths. All Y–Ge bond lengths are 3.29 Å. In the second Y site, Y is bonded in a 9-coordinate geometry to one Y, nine equivalent Rh, and three equivalent Ge atoms. The Y–Y bond length is 3.32 Å. There are three shorter (3.05 Å) and six longer (3.14 Å) Y–Rh bond lengths. All Y–Ge bond lengths are 3.29 Å. In the third Y site, Y is bonded in a 6-coordinate geometry to two Y, twelve equivalent Rh, and six Ge atoms. All Y–Rh bond lengths are 3.39 Å. All Y–Ge bond lengths are 3.24 Å. Rh is bonded in a 12-coordinate geometry to five Y, four equivalent Rh, and three Ge atoms. There are two shorter (2.78 Å) and two longer (2.82 Å) Rh–Rh bond lengths. There are a spread of Rh–Ge bond distances ranging from 2.50–2.58 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to three equivalent Y and six equivalent Rh atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to three equivalent Y and six equivalent Rh atoms. In the third Ge site, Ge is bonded to six Y and six equivalent Rh atoms to form distorted edge-sharing GeY6Rh6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na4Ga8Ge15 by Materials Project

Na4Ga8Ge15 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a distorted body-centered cubic geometry to eight equivalent Ga atoms. All Na–Ga bond lengths are 3.43 Å. In the second Na site, Na is bonded in a 8-coordinate geometry to eight equivalent Ge atoms. All Na–Ge bond lengths are 3.62 Å. Ga is bonded in a 3-coordinate geometry to one Na, one Ga, and three equivalent Ge atoms. The Ga–Ga bond length is 2.55 Å. All Ga–Ge bond lengths are 2.53 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a tetrahedral geometry to four equivalent Ge atoms. All Ge–Ge bond lengths are 2.52 Å. In the second Ge site, Ge is bonded in a 4-coordinate geometry to two equivalent Na, two equivalent Ga, and two Ge atoms. The Ge–Ge bond length is 2.50 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu5Ge2 by Materials Project

Cu5Ge2 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Cu sites. In the first Cu site, Cu is bonded in a 11-coordinate geometry to five Cu and six Ge atoms. There are a spread of Cu–Cu bond distances ranging from 2.44–2.58 Å. There are three shorter (2.78 Å) and three longer (2.85 Å) Cu–Ge bond lengths. In the second Cu site, Cu is bonded in a 10-coordinate geometry to seven Cu and three equivalent Ge atoms. There are a spread of Cu–Cu bond distances ranging from 2.44–2.58 Å. All Cu–Ge bond lengths are 2.84 Å. In the third Cu site, Cu is bonded in a 8-coordinate geometry to four Cu and four Ge atoms. There are one shorter (2.56 Å) and three longer (2.57 Å) Cu–Ge bond lengths. In the fourth Cu site, Cu is bonded in a 4-coordinate geometry to four Cu and four Ge atoms. There are three shorter (2.45 Å) and one longer (2.46 Å) Cu–Ge bond lengths. In the fifth Cu site, Cu is bonded in a distorted body-centered cubic geometry to four Cu and four Ge atoms. There are one shorter (2.56 Å) and three longer (2.57 Å) Cu–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 11-coordinate geometry to eleven Cu atoms. In the second Ge site, Ge is bonded in a 10-coordinate geometry to ten Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ni7Ge4 by Materials Project

Ni7Ge4 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a 8-coordinate geometry to eight Ni and six Ge atoms. There are a spread of Ni–Ni bond distances ranging from 2.53–2.62 Å. There are three shorter (2.62 Å) and three longer (2.63 Å) Ni–Ge bond lengths. In the second Ni site, Ni is bonded in a 11-coordinate geometry to five Ni and six Ge atoms. There are one shorter (2.42 Å) and three longer (2.61 Å) Ni–Ni bond lengths. There are three shorter (2.59 Å) and three longer (2.60 Å) Ni–Ge bond lengths. In the third Ni site, Ni is bonded in a 5-coordinate geometry to six equivalent Ni and five Ge atoms. There are three shorter (2.29 Å) and two longer (2.57 Å) Ni–Ge bond lengths. In the fourth Ni site, Ni is bonded in a 5-coordinate geometry to six Ni and five Ge atoms. There are a spread of Ni–Ge bond distances ranging from 2.29–2.55 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to ten Ni atoms. In the second Ge site, Ge is bonded in a 8-coordinate geometry to eight Ni atoms. In the third Ge site, Ge is bonded in a 11-coordinate geometry to eleven Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrGe3 by Materials Project

SrGe3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 12-coordinate geometry to twelve Ge atoms. There are a spread of Sr–Ge bond distances ranging from 3.35–3.61 Å. In the second Sr site, Sr is bonded in a 12-coordinate geometry to twelve Ge atoms. There are four shorter (3.30 Å) and eight longer (3.36 Å) Sr–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four Sr and five Ge atoms. There are one shorter (2.55 Å) and four longer (2.81 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four Sr and five Ge atoms. There are one shorter (2.60 Å) and two longer (2.83 Å) Ge–Ge bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiCa7(GeH)3 by Materials Project

LiCa7(GeH)3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li is bonded in a distorted linear geometry to two equivalent Ge and two H atoms. There are one shorter (2.80 Å) and one longer (2.99 Å) Li–Ge bond lengths. There are one shorter (2.11 Å) and one longer (2.13 Å) Li–H bond lengths. There are four inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to four Ge and two H atoms. There are a spread of Ca–Ge bond distances ranging from 2.96–3.55 Å. There are one shorter (2.59 Å) and one longer (2.61 Å) Ca–H bond lengths. In the second Ca site, Ca is bonded in a 6-coordinate geometry to four Ge and two H atoms. There are a spread of Ca–Ge bond distances ranging from 2.93–3.54 Å. There are one shorter (2.62 Å) and one longer (2.65 Å) Ca–H bond lengths. In the third Ca site, Ca is bonded in a 5-coordinate geometry to four Ge and two H atoms. There are a spread of Ca–Ge bond distances ranging from 2.93–3.68 Å. There are one shorter (2.49 Å) and one longer (2.59 Å) Ca–H bond lengths. In the fourth Ca site, Ca is bonded in a 7-coordinate geometry to three Ge and four H atoms. There are two shorter (3.10 Å) and one longer (3.33 Å) Ca–Ge bond lengths. There are a spread of Ca–H bond distances ranging from 2.44–2.57 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to ten Ca atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Li and seven Ca atoms. There are three inequivalent H sites. In the first H site, H is bonded to one Li and five Ca atoms to form a mixture of face and corner-sharing HLiCa5 octahedra. The corner-sharing octahedra tilt angles range from 1–45°. In the second H site, H is bonded to six Ca atoms to form HCa6 octahedra that share corners with four HCa6 octahedra and faces with two HLiCa5 octahedra. The corner-sharing octahedra tilt angles range from 22–45°. In the third H site, H is bonded to one Li and five Ca atoms to form a mixture of distorted face and corner-sharing HLiCa5 octahedra. The corner-sharing octahedra tilt angles range from 1–45°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Er3Ga2Ge3 by Materials Project

Er3Ga2Ge3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 5-coordinate geometry to four equivalent Ga and five Ge atoms. There are two shorter (2.82 Å) and two longer (3.10 Å) Er–Ga bond lengths. There are a spread of Er–Ge bond distances ranging from 2.87–3.30 Å. In the second Er site, Er is bonded in a 10-coordinate geometry to four equivalent Ga and six Ge atoms. There are two shorter (3.06 Å) and two longer (3.14 Å) Er–Ga bond lengths. There are a spread of Er–Ge bond distances ranging from 2.96–3.19 Å. Ga is bonded in a 10-coordinate geometry to six Er, one Ga, and three Ge atoms. The Ga–Ga bond length is 2.81 Å. There are two shorter (2.68 Å) and one longer (2.81 Å) Ga–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six Er, two equivalent Ga, and one Ge atom. The Ge–Ge bond length is 2.66 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to five Er, two equivalent Ga, and two equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sm11(In3Ge2)2 by Materials Project

Sm11Ge4In6 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are four inequivalent Sm sites. In the first Sm site, Sm is bonded in a 9-coordinate geometry to eight In and one Ge atom. All Sm–In bond lengths are 3.46 Å. The Sm–Ge bond length is 3.55 Å. In the second Sm site, Sm is bonded to four equivalent In and three Ge atoms to form a mixture of distorted edge, face, and corner-sharing SmIn4Ge3 pentagonal bipyramids. There are two shorter (3.43 Å) and two longer (3.51 Å) Sm–In bond lengths. There are a spread of Sm–Ge bond distances ranging from 3.12–3.29 Å. In the third Sm site, Sm is bonded in a 5-coordinate geometry to four In and three Ge atoms. There are two shorter (3.17 Å) and two longer (3.40 Å) Sm–In bond lengths. There are two shorter (3.06 Å) and one longer (3.09 Å) Sm–Ge bond lengths. In the fourth Sm site, Sm is bonded in a 7-coordinate geometry to three In and four Ge atoms. There are one shorter (3.39 Å) and two longer (3.51 Å) Sm–In bond lengths. There are two shorter (2.89 Å) and two longer (3.45 Å) Sm–Ge bond lengths. There are two inequivalent In sites. In the first In site, In is bonded in a 10-coordinate geometry to eight Sm and two In atoms. There are one shorter (2.98 Å) and one longer (3.11 Å) In–In bond lengths. In the second In site, In is bonded in a 11-coordinate geometry to seven Sm and four In atoms. Both In–In bond lengths are 3.04 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to eight Sm atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to nine Sm atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to eight Sm atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2NiGe3 by Materials Project

Pr2NiGe3 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pr is bonded to three equivalent Ni and nine Ge atoms to form a mixture of edge and face-sharing PrNi3Ge9 cuboctahedra. All Pr–Ni bond lengths are 3.12 Å. There are three shorter (3.12 Å) and six longer (3.34 Å) Pr–Ge bond lengths. Ni is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms. All Ni–Ge bond lengths are 2.46 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms. All Ge–Ge bond lengths are 2.46 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ni atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaGe3 by Materials Project

BaGe3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 12-coordinate geometry to twelve Ge atoms. There are a spread of Ba–Ge bond distances ranging from 3.51–3.70 Å. In the second Ba site, Ba is bonded in a 12-coordinate geometry to twelve Ge atoms. There are four shorter (3.47 Å) and eight longer (3.51 Å) Ba–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four Ba and five Ge atoms. There are one shorter (2.54 Å) and four longer (2.83 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four Ba and five Ge atoms. There are one shorter (2.53 Å) and two longer (2.88 Å) Ge–Ge bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y11(In3Ge2)2 by Materials Project

Y11(In3Ge2)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are four inequivalent Y sites. In the first Y site, Y is bonded in a 7-coordinate geometry to four equivalent In and three Ge atoms. There are two shorter (3.39 Å) and two longer (3.45 Å) Y–In bond lengths. There are a spread of Y–Ge bond distances ranging from 3.10–3.26 Å. In the second Y site, Y is bonded in a 5-coordinate geometry to four In and three Ge atoms. There are two shorter (3.10 Å) and two longer (3.37 Å) Y–In bond lengths. All Y–Ge bond lengths are 3.02 Å. In the third Y site, Y is bonded in a 7-coordinate geometry to three In and four Ge atoms. There are one shorter (3.31 Å) and two longer (3.47 Å) Y–In bond lengths. There are two shorter (2.85 Å) and two longer (3.34 Å) Y–Ge bond lengths. In the fourth Y site, Y is bonded in a 9-coordinate geometry to eight In and one Ge atom. There are four shorter (3.38 Å) and four longer (3.44 Å) Y–In bond lengths. The Y–Ge bond length is 3.64 Å. There are two inequivalent In sites. In the first In site, In is bonded in a 10-coordinate geometry to eight Y and two In atoms. There are one shorter (2.97 Å) and one longer (3.08 Å) In–In bond lengths. In the second In site, In is bonded in a 11-coordinate geometry to seven Y and four In atoms. Both In–In bond lengths are 2.99 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to eight Y atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to nine Y atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to eight Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce2CuGe3 by Materials Project

Ce2CuGe3 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ce is bonded to three equivalent Cu and nine Ge atoms to form a mixture of edge and face-sharing CeCu3Ge9 cuboctahedra. All Ce–Cu bond lengths are 3.16 Å. There are three shorter (3.16 Å) and six longer (3.18 Å) Ce–Ge bond lengths. Cu is bonded in a 9-coordinate geometry to six equivalent Ce and three equivalent Ge atoms. All Cu–Ge bond lengths are 2.47 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Ce and three equivalent Ge atoms. All Ge–Ge bond lengths are 2.47 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Ce and three equivalent Cu atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Ce and three equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Co7Ge4 by Materials Project

Co7Ge4 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are four inequivalent Co sites. In the first Co site, Co is bonded in a 11-coordinate geometry to five Co and six Ge atoms. There are a spread of Co–Co bond distances ranging from 2.38–2.61 Å. There are three shorter (2.59 Å) and three longer (2.64 Å) Co–Ge bond lengths. In the second Co site, Co is bonded in a 8-coordinate geometry to eight Co and six Ge atoms. There are a spread of Co–Co bond distances ranging from 2.49–2.64 Å. All Co–Ge bond lengths are 2.62 Å. In the third Co site, Co is bonded to six equivalent Co and five Ge atoms to form a mixture of distorted corner and face-sharing CoCo6Ge5 trigonal bipyramids. There are three shorter (2.30 Å) and two longer (2.49 Å) Co–Ge bond lengths. In the fourth Co site, Co is bonded to six Co and five Ge atoms to form a mixture of distorted corner and face-sharing CoCo6Ge5 trigonal bipyramids. There are a spread of Co–Ge bond distances ranging from 2.30–2.54 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to ten Co atoms. In the second Ge site, Ge is bonded in a 8-coordinate geometry to eight Co atoms. In the third Ge site, Ge is bonded in a 11-coordinate geometry to eleven Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K7NaGe8 by Materials Project

K7NaGe8 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of K–Ge bond distances ranging from 3.41–3.68 Å. In the second K site, K is bonded in a distorted octahedral geometry to six equivalent Ge atoms. All K–Ge bond lengths are 3.96 Å. Na is bonded in a 6-coordinate geometry to six equivalent Ge atoms. All Na–Ge bond lengths are 2.95 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to five K, one Na, and three Ge atoms. There are one shorter (2.57 Å) and two longer (2.66 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent K and three equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Co12Ge4C by Materials Project

Co12Ge4C crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are five inequivalent Co sites. In the first Co site, Co is bonded in a single-bond geometry to four equivalent Co, four equivalent Ge, and one C atom. All Co–Co bond lengths are 2.53 Å. All Co–Ge bond lengths are 2.59 Å. The Co–C bond length is 1.86 Å. In the second Co site, Co is bonded to eight Co and four equivalent Ge atoms to form CoCo8Ge4 cuboctahedra that share corners with eight equivalent CoCo8Ge4 cuboctahedra, edges with eight GeCo12 cuboctahedra, edges with sixteen CoCo8Ge4 cuboctahedra, faces with four equivalent GeCo12 cuboctahedra, and faces with thirteen CoCo8Ge4 cuboctahedra. There are four shorter (2.51 Å) and four longer (2.52 Å) Co–Co bond lengths. All Co–Ge bond lengths are 2.58 Å. In the third Co site, Co is bonded in a linear geometry to four equivalent Ge and two equivalent C atoms. All Co–Ge bond lengths are 2.66 Å. Both Co–C bond lengths are 1.83 Å. In the fourth Co site, Co is bonded to eight Co and four Ge atoms to form distorted CoCo8Ge4 cuboctahedra that share corners with eight CoCo8Ge4 cuboctahedra, corners with two equivalent CCo6 octahedra, edges with eight CoCo8Ge4 cuboctahedra, edges with eight GeCo12 cuboctahedra, faces with four GeCo12 cuboctahedra, and faces with eleven CoCo8Ge4 cuboctahedra. The corner-sharing octahedral tilt angles are 46°. All Co–Co bond lengths are 2.58 Å. There are two shorter (2.48 Å) and two longer (2.53 Å) Co–Ge bond lengths. In the fifth Co site, Co is bonded to eight Co and four equivalent Ge atoms to form CoCo8Ge4 cuboctahedra that share corners with twelve CoCo8Ge4 cuboctahedra, edges with eight equivalent GeCo12 cuboctahedra, edges with sixteen CoCo8Ge4 cuboctahedra, faces with four equivalent GeCo12 cuboctahedra, and faces with fourteen CoCo8Ge4 cuboctahedra. All Co–Co bond lengths are 2.58 Å. All Co–Ge bond lengths are 2.50 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded to twelve Co atoms to form GeCo12 cuboctahedra that share corners with twelve GeCo12 cuboctahedra, edges with twelve CoCo8Ge4 cuboctahedra, faces with four equivalent CoCo8Ge4 cuboctahedra, faces with six GeCo12 cuboctahedra, and faces with four equivalent CCo6 octahedra. In the second Ge site, Ge is bonded to twelve Co atoms to form GeCo12 cuboctahedra that share corners with twelve GeCo12 cuboctahedra, edges with twenty CoCo8Ge4 cuboctahedra, faces with six GeCo12 cuboctahedra, and faces with twelve CoCo8Ge4 cuboctahedra. C is bonded to six Co atoms to form CCo6 octahedra that share corners with eight equivalent CoCo8Ge4 cuboctahedra, corners with four equivalent CCo6 octahedra, and faces with eight equivalent GeCo12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Heavy boron doping effects on biaxially tensile strained germanium (>1.5%) investigated via structural characterization, effective lifetime assessment and atomistic modeling

Highly tensile strained germanium (ε-Ge) represents an essential material system for emerging electronic and photonics applications. Moreover, adjusting the doping levels to moderate or high concentrations can effectively tailor the properties of ε-Ge for specific applications. This article combines experimental characterization with a theoretical framework to examine the effects of heavy elemental boron (B) doping on pseudomorphic sub-50 nm ε-Ge. High resolution X-ray diffractometry is used to validate tensile strain levels of 1.53% and 1.68% in Ge epilayers, surpassing the indirect-to-direct band gap crossover point at ∼1.5% biaxial tensile strain. Cross-sectional transmission electron microscopy revealed visual evidence of stacking faults and surface roughening in 1.68% ε-Ge, although a coherent and abrupt Ge/III–V heterointerface is observed, devoid of interfacial misfit dislocations. Effective lifetime measurements demonstrated approximately twofold enhancement in 1.53% B-doped ε-Ge (N B ∼7 × 10 19 cm −3 ) compared to its unstrained B-doped counterpart, while no such improvement was observed in 1.68% B-doped ε-Ge. This lack of enhancement is attributed to the presence of stacking faults and surface roughness within the ε-Ge epilayer. Through density functional theory calculations, we independently demonstrate that substitutional B atoms induce local deformation of Ge–Ge bonds in both unstrained Ge and ε-Ge epilayers, resulting in an additive tensile strain. This phenomenon could potentially lead to dynamic reduction and overcoming of the critical layer thickness for the system, facilitating the nucleation and subsequent glide of 90° leading Shockley partial dislocations, thereby generating stacking faults. In essence, these findings establish an upper limit on the B-doping concentration that can be achieved in highly ε-Ge epilayers, and collectively, offer valuable insights into the significance of heavy doping in Ge-based heterostructures. As such, this study delineates a fundamental constraint for integrating heavily doped ε-Ge in high-performance optoelectronic systems, necessitating precise strain-doping co-optimization to avoid performance degradation.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2020

Materials Data on Hf3(NiGe)4 by Materials Project

Hf3Ni4Ge4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to six equivalent Ni and six Ge atoms. All Hf–Ni bond lengths are 2.84 Å. There are two shorter (2.84 Å) and four longer (2.87 Å) Hf–Ge bond lengths. In the second Hf site, Hf is bonded to eight equivalent Ni and six Ge atoms to form face-sharing HfNi8Ge6 octahedra. All Hf–Ni bond lengths are 3.28 Å. There are two shorter (2.75 Å) and four longer (2.77 Å) Hf–Ge bond lengths. Ni is bonded in a 12-coordinate geometry to five Hf, three equivalent Ni, and four Ge atoms. There are one shorter (2.61 Å) and two longer (2.79 Å) Ni–Ni bond lengths. There are a spread of Ni–Ge bond distances ranging from 2.38–2.41 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to three Hf and six equivalent Ni atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Hf, two equivalent Ni, and one Ge atom. The Ge–Ge bond length is 2.61 Å.

36 MATERIALS SCIENCE↗