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Materials Data on Cr(GaS2)2 by Materials Project

Cr(GaS2)2 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Cr2+ is bonded to four equivalent S2- atoms to form CrS4 tetrahedra that share corners with twelve equivalent GaS6 octahedra. The corner-sharing octahedral tilt angles are 55°. All Cr–S bond lengths are 2.19 Å. Ga3+ is bonded to six equivalent S2- atoms to form GaS6 octahedra that share corners with six equivalent CrS4 tetrahedra and edges with six equivalent GaS6 octahedra. All Ga–S bond lengths are 2.53 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to one Cr2+ and three equivalent Ga3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(InS2)2 by Materials Project

Cr(InS2)2 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Cr2+ is bonded to four equivalent S2- atoms to form CrS4 tetrahedra that share corners with twelve equivalent InS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Cr–S bond lengths are 2.39 Å. In3+ is bonded to six equivalent S2- atoms to form InS6 octahedra that share corners with six equivalent CrS4 tetrahedra and edges with six equivalent InS6 octahedra. All In–S bond lengths are 2.66 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to one Cr2+ and three equivalent In3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(GeO3)2 by Materials Project

Cr(GeO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Cr4+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with three equivalent GeO4 tetrahedra, corners with two equivalent GeO5 trigonal bipyramids, edges with two equivalent CrO6 octahedra, and an edgeedge with one GeO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 1.82–2.10 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three equivalent CrO6 octahedra and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–60°. There are a spread of Ge–O bond distances ranging from 1.75–1.79 Å. In the second Ge4+ site, Ge4+ is bonded to five O2- atoms to form distorted GeO5 trigonal bipyramids that share corners with two equivalent CrO6 octahedra, corners with two equivalent GeO5 trigonal bipyramids, an edgeedge with one CrO6 octahedra, and an edgeedge with one GeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 36–41°. There are a spread of Ge–O bond distances ranging from 1.76–2.05 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cr4+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Ge4+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Ge4+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Cr4+ and two equivalent Ge4+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr4+ and one Ge4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cr4+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Cr(Fe2Sb5)2 by Materials Project

Cr(Fe2Sb5)2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. Cr6+ is bonded to six Sb+1.80- atoms to form CrSb6 octahedra that share corners with eight FeSb6 octahedra and edges with two equivalent CrSb6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are one shorter (2.67 Å) and five longer (2.68 Å) Cr–Sb bond lengths. There are five inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six Sb+1.80- atoms to form a mixture of corner and edge-sharing FeSb6 octahedra. The corner-sharing octahedra tilt angles range from 50–51°. There are a spread of Fe–Sb bond distances ranging from 2.58–2.61 Å. In the second Fe3+ site, Fe3+ is bonded to six Sb+1.80- atoms to form a mixture of corner and edge-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are two shorter (2.59 Å) and four longer (2.61 Å) Fe–Sb bond lengths. In the third Fe3+ site, Fe3+ is bonded to six Sb+1.80- atoms to form FeSb6 octahedra that share corners with four equivalent CrSb6 octahedra, corners with four equivalent FeSb6 octahedra, and edges with two equivalent FeSb6 octahedra. The corner-sharing octahedra tilt angles range from 50–51°. There are a spread of Fe–Sb bond distances ranging from 2.55–2.60 Å. In the fourth Fe3+ site, Fe3+ is bonded to six Sb+1.80- atoms to form FeSb6 octahedra that share corners with eight equivalent CrSb6 octahedra and edges with two equivalent FeSb6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are two shorter (2.52 Å) and four longer (2.57 Å) Fe–Sb bond lengths. In the fifth Fe3+ site, Fe3+ is bonded to six Sb+1.80- atoms to form a mixture of corner and edge-sharing FeSb6 octahedra. The corner-sharing octahedra tilt angles range from 50–51°. There are a spread of Fe–Sb bond distances ranging from 2.59–2.61 Å. There are ten inequivalent Sb+1.80- sites. In the first Sb+1.80- site, Sb+1.80- is bonded in a 3-coordinate geometry to one Cr6+ and two equivalent Fe3+ atoms. In the second Sb+1.80- site, Sb+1.80- is bonded in a 3-coordinate geometry to one Cr6+ and two equivalent Fe3+ atoms. In the third Sb+1.80- site, Sb+1.80- is bonded in a 4-coordinate geometry to three Fe3+ atoms. In the fourth Sb+1.80- site, Sb+1.80- is bonded in a 6-coordinate geometry to three Fe3+ atoms. In the fifth Sb+1.80- site, Sb+1.80- is bonded in a 6-coordinate geometry to three Fe3+ atoms. In the sixth Sb+1.80- site, Sb+1.80- is bonded in a 3-coordinate geometry to two equivalent Cr6+ and one Fe3+ atom. In the seventh Sb+1.80- site, Sb+1.80- is bonded in a 3-coordinate geometry to two equivalent Cr6+ and one Fe3+ atom. In the eighth Sb+1.80- site, Sb+1.80- is bonded in a 3-coordinate geometry to three Fe3+ atoms. In the ninth Sb+1.80- site, Sb+1.80- is bonded in a 6-coordinate geometry to three Fe3+ atoms. In the tenth Sb+1.80- site, Sb+1.80- is bonded in a 6-coordinate geometry to three Fe3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(InS2)2 by Materials Project

Cr(InS2)2 is Spinel-like structured and crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Cr2+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with six equivalent InS4 tetrahedra, edges with two equivalent CrS6 octahedra, and edges with four equivalent InS6 octahedra. There are two shorter (2.45 Å) and four longer (2.48 Å) Cr–S bond lengths. There are two inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to four S2- atoms to form InS4 tetrahedra that share corners with six equivalent CrS6 octahedra and corners with six equivalent InS6 octahedra. The corner-sharing octahedra tilt angles range from 52–67°. There are two shorter (2.58 Å) and two longer (2.60 Å) In–S bond lengths. In the second In3+ site, In3+ is bonded to six S2- atoms to form InS6 octahedra that share corners with six equivalent InS4 tetrahedra, edges with two equivalent InS6 octahedra, and edges with four equivalent CrS6 octahedra. All In–S bond lengths are 2.65 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one Cr2+ and three In3+ atoms. In the second S2- site, S2- is bonded to two equivalent Cr2+ and two In3+ atoms to form a mixture of distorted corner and edge-sharing SCr2In2 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Cr(SbO3)2 by Materials Project

Cr(SbO3)2 is zeta iron carbide-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cr6+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with twelve equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 50–54°. There are two shorter (2.13 Å) and four longer (2.33 Å) Cr–O bond lengths. Sb3+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with six equivalent CrO6 octahedra and edges with three equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of Sb–O bond distances ranging from 2.01–2.04 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cr6+ and two equivalent Sb3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cr6+ and two equivalent Sb3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(FeSe2)2 by Materials Project

Cr(FeSe2)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with twelve equivalent FeSe6 octahedra, edges with two equivalent CrSe6 octahedra, and faces with two equivalent FeSe6 octahedra. The corner-sharing octahedra tilt angles range from 53–56°. There are two shorter (2.53 Å) and four longer (2.56 Å) Cr–Se bond lengths. Fe+2.50+ is bonded to six Se2- atoms to form FeSe6 octahedra that share corners with six equivalent CrSe6 octahedra, edges with six equivalent FeSe6 octahedra, and a faceface with one CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 53–56°. There are a spread of Fe–Se bond distances ranging from 2.40–2.67 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Cr3+ and three equivalent Fe+2.50+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cr3+ and three equivalent Fe+2.50+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(RhSe2)2 by Materials Project

Cr(RhSe2)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cr2+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with twelve equivalent RhSe6 octahedra, edges with two equivalent CrSe6 octahedra, and faces with two equivalent RhSe6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are four shorter (2.58 Å) and two longer (2.62 Å) Cr–Se bond lengths. Rh3+ is bonded to six Se2- atoms to form RhSe6 octahedra that share corners with six equivalent CrSe6 octahedra, edges with six equivalent RhSe6 octahedra, and a faceface with one CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of Rh–Se bond distances ranging from 2.47–2.62 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Cr2+ and three equivalent Rh3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Cr2+ and three equivalent Rh3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(Te2Rh)2 by Materials Project

Cr(RhTe2)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cr2+ is bonded to six Te2- atoms to form CrTe6 octahedra that share corners with twelve equivalent RhTe6 octahedra, edges with two equivalent CrTe6 octahedra, and faces with two equivalent RhTe6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are four shorter (2.78 Å) and two longer (2.80 Å) Cr–Te bond lengths. Rh3+ is bonded to six Te2- atoms to form RhTe6 octahedra that share corners with six equivalent CrTe6 octahedra, edges with six equivalent RhTe6 octahedra, and a faceface with one CrTe6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Rh–Te bond distances ranging from 2.67–2.76 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Cr2+ and three equivalent Rh3+ atoms. In the second Te2- site, Te2- is bonded in a 4-coordinate geometry to one Cr2+ and three equivalent Rh3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(ReO3)2 by Materials Project

Cr(ReO3)2 is beta Vanadium nitride-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with eight equivalent ReO6 octahedra and edges with two equivalent ReO6 octahedra. The corner-sharing octahedra tilt angles range from 41–51°. There is two shorter (1.89 Å) and four longer (2.00 Å) Cr–O bond length. Re+4.50+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with four equivalent CrO6 octahedra, corners with four equivalent ReO6 octahedra, an edgeedge with one CrO6 octahedra, and an edgeedge with one ReO6 octahedra. The corner-sharing octahedra tilt angles range from 41–51°. There are a spread of Re–O bond distances ranging from 1.97–2.04 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+ and two equivalent Re+4.50+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Cr3+ and two equivalent Re+4.50+ atoms.

36 MATERIALS SCIENCE↗

Microstructural examination of interactions between chromia-based refractory and nuclear glass in a melter

This study shows the effects of nuclear waste glass production on Monofrax K-3 refractory corrosion. A continuously fed research-scale melter containing an Fe- and Ni-rich simulated nuclear waste feed with borosilicate glass-forming chemicals was cyclically melted at 1150°C and idled at 1050°C for a total of 11 weeks. Chemical maps using scanning electron microscopy show the interactions between the quenched melt and the refractory. Nanoscale X-ray-computed tomography was used for a three-dimensional visualization of certain parts of the interface. Unreacted K-3 consists of primarily corundum (Al,Cr) 2 O 3 and spinel (Fe 2+ ,Mg)(Al,Cr) 2 O 4 interlocking crystalline phases. Some of the Cr from the refractory interacts with the Ni and Fe from the melt to form a reaction layer comprising (Ni,Fe 2+ )(Cr,Fe 3+ ) 2 O 4 spinel crystals. Simultaneously, melt components (Na,Si) infiltrate into the refractory. This interaction proceeds at the expense of the integrity of the refractory structure. Intact refractory grains (e.g., (Al,Cr) 2 O 3 ) as well as the reaction layer itself can lose mechanical integrity and spall off into the melt, especially near the top of the melter. As the reaction layer can be a protective boundary for the refractory against further melt infiltration, a reduction in the reaction layer thickness allows an increase in refractory corrosion.

36 MATERIALS SCIENCE↗

Materials Data on Cr(Mo3Se4)2 by Materials Project

Cr(Mo3Se4)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Mo+2.17+ sites. In the first Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of edge and corner-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.55–2.70 Å. In the second Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of edge and corner-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.54–2.70 Å. In the third Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of edge and corner-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.55–2.71 Å. Cr3+ is bonded in a body-centered cubic geometry to eight Se2- atoms. There are a spread of Cr–Se bond distances ranging from 2.51–3.16 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four Mo+2.17+ and one Cr3+ atom. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to three Mo+2.17+ and one Cr3+ atom. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to four Mo+2.17+ and one Cr3+ atom. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Mo+2.17+ and one Cr3+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Cr(MoS2)2 by Materials Project

Cr(MoS2)2 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Mo+2.50+ sites. In the first Mo+2.50+ site, Mo+2.50+ is bonded to six S2- atoms to form distorted MoS6 octahedra that share corners with six CrS6 octahedra, edges with six MoS6 octahedra, and a faceface with one CrS6 octahedra. The corner-sharing octahedra tilt angles range from 47–56°. There are a spread of Mo–S bond distances ranging from 2.37–2.61 Å. In the second Mo+2.50+ site, Mo+2.50+ is bonded to six S2- atoms to form distorted MoS6 octahedra that share corners with six CrS6 octahedra, edges with six MoS6 octahedra, and a faceface with one CrS6 octahedra. The corner-sharing octahedra tilt angles range from 48–57°. There are a spread of Mo–S bond distances ranging from 2.37–2.61 Å. In the third Mo+2.50+ site, Mo+2.50+ is bonded to six S2- atoms to form distorted MoS6 octahedra that share corners with six CrS6 octahedra, edges with six MoS6 octahedra, and a faceface with one CrS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Mo–S bond distances ranging from 2.38–2.64 Å. In the fourth Mo+2.50+ site, Mo+2.50+ is bonded to six S2- atoms to form distorted MoS6 octahedra that share corners with six CrS6 octahedra, edges with six MoS6 octahedra, and a faceface with one CrS6 octahedra. The corner-sharing octahedra tilt angles range from 48–58°. There are a spread of Mo–S bond distances ranging from 2.37–2.64 Å. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with twelve MoS6 octahedra, edges with two equivalent CrS6 octahedra, and faces with two MoS6 octahedra. The corner-sharing octahedra tilt angles range from 47–59°. There are a spread of Cr–S bond distances ranging from 2.45–2.51 Å. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with twelve MoS6 octahedra, edges with two equivalent CrS6 octahedra, and faces with two MoS6 octahedra. The corner-sharing octahedra tilt angles range from 48–58°. There are a spread of Cr–S bond distances ranging from 2.45–2.53 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Mo+2.50+ and two Cr3+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three Mo+2.50+ and two Cr3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to three Mo+2.50+ and one Cr3+ atom. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to three Mo+2.50+ and one Cr3+ atom. In the fifth S2- site, S2- is bonded in a 4-coordinate geometry to three Mo+2.50+ and one Cr3+ atom. In the sixth S2- site, S2- is bonded in a 4-coordinate geometry to three Mo+2.50+ and one Cr3+ atom. In the seventh S2- site, S2- is bonded in a 5-coordinate geometry to three Mo+2.50+ and two Cr3+ atoms. In the eighth S2- site, S2- is bonded in a 5-coordinate geometry to three Mo+2.50+ and two Cr3+ atoms.

36 MATERIALS SCIENCE↗

Effect of Soluble Corrosion Products on Electrical Double Layer in LiCl-KCl Molten Salts

Corrosion in molten salts greatly hampers the application for renewable energy applications like molten salt reactors. To develop effective strategies for corrosion mitigation, understanding the interfacial structures and properties such as specific ion adsorption and electrical double layer capacitance are crucial. Using cyclic voltammetry and electrochemical impedance spectroscopy, we systematically studied the interfaces on various model electrodes including W (solid), Bi (liquid), and the stainless steel 316 in LiCl-KCl eutectic molten salts with the addition of corrosion species CrCl 2 and FeCl 2 . Both Cr 2+ and Fe 2+ ions increased electrical double layer capacitance, with Cr 2+ showing specific adsorption behavior and shifting the potential of zero charge, while Fe 2+ had minimal effect on point of zero charge. Two-working electrode measurements revealed increasing open-circuit potential and electrical double layer capacitance during the exposure of stainless steel 316, indicating its progressive corrosion and ion accumulation at the interface. X-ray photoelectron spectroscopy and Raman confirmed Cr enrichment at the interface. This work highlights the strong correlation between electrical double layer behavior and corrosion dynamics in molten salts and suggests electrical double layer capacitance as a sensitive, in situ indicator for corrosion monitoring.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Materials Data on Cr(PO3)2 by Materials Project

Cr(PO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Cr–O bond distances ranging from 2.08–2.13 Å. In the second Cr2+ site, Cr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cr–O bond distances ranging from 2.07–2.43 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.47–1.63 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.62 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Cr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Cr2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Cr2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cr(BMo)2 by Materials Project

Cr(MoB)2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mo2+ is bonded in a distorted hexagonal planar geometry to six equivalent B3- atoms. There are two shorter (2.33 Å) and four longer (2.34 Å) Mo–B bond lengths. Cr2+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Cr–B bond lengths are 2.35 Å. B3- is bonded in a 9-coordinate geometry to six equivalent Mo2+, two equivalent Cr2+, and one B3- atom. The B–B bond length is 1.88 Å.

36 MATERIALS SCIENCE↗

Materials Data on Cr(FeAs3)2 by Materials Project

Cr(FeAs3)2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. Cr4+ is bonded to six As+1.67- atoms to form CrAs6 octahedra that share corners with eight FeAs6 octahedra and edges with two equivalent CrAs6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are five shorter (2.47 Å) and one longer (2.49 Å) Cr–As bond lengths. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six As+1.67- atoms to form a mixture of edge and corner-sharing FeAs6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are two shorter (2.39 Å) and four longer (2.40 Å) Fe–As bond lengths. In the second Fe3+ site, Fe3+ is bonded to six As+1.67- atoms to form FeAs6 octahedra that share corners with four equivalent CrAs6 octahedra, corners with four equivalent FeAs6 octahedra, and edges with two equivalent FeAs6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Fe–As bond distances ranging from 2.37–2.41 Å. In the third Fe3+ site, Fe3+ is bonded to six As+1.67- atoms to form FeAs6 octahedra that share corners with eight equivalent CrAs6 octahedra and edges with two equivalent FeAs6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are two shorter (2.35 Å) and four longer (2.37 Å) Fe–As bond lengths. There are six inequivalent As+1.67- sites. In the first As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to one Cr4+ and two equivalent Fe3+ atoms. In the second As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to one Cr4+ and two equivalent Fe3+ atoms. In the third As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to three Fe3+ atoms. In the fourth As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to two equivalent Cr4+ and one Fe3+ atom. In the fifth As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to two equivalent Cr4+ and one Fe3+ atom. In the sixth As+1.67- site, As+1.67- is bonded in a 4-coordinate geometry to three Fe3+ atoms.

36 MATERIALS SCIENCE↗

Additives for lithium batteries and methods

Lithium tetrafluoro(malonato)phosphate compounds are useful as additives in lithium ion battery applications. The compounds are represented by Formula (I): MPF4[—O(C═O)—(CX′X″)—(C═O)O—]; wherein M is Li or Na; each X′ and X″ independently is selected from the group consisting of H, alkyl, fluoro-substituted alkyl, and F; or wherein the X′ and X″ together are —CR2—(CR′2)m—CR″2—; each R, R′ and R″ independently is selected from the group consisting of H, methyl, trifluoromethyl, and F; and m is 0 or 1. These compounds can be prepared in high purity and a high yield by reaction of a metal hexafluorophosphate with a bis-silyl malonate compound. A similar oxalato compound, lithium tetrafluoro(oxalato)phosphate), can be made in the same manner, but using a bis-silyl oxalate in place of the bis-silyl malonate. Advantageously, the compounds can be formed, in situ, in a LiPF6-containing electrolyte solution.

Liao, Chen↗