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DOE OSTI2020

Materials Data on TbNdCo14B by Materials Project

TbNdCo14B is beta Uranium-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Tb is bonded in a 12-coordinate geometry to sixteen Co and two equivalent B atoms. There are a spread of Tb–Co bond distances ranging from 2.92–3.22 Å. Both Tb–B bond lengths are 3.10 Å. Nd is bonded in a 11-coordinate geometry to sixteen Co and one B atom. There are a spread of Nd–Co bond distances ranging from 2.97–3.30 Å. The Nd–B bond length is 2.84 Å. There are six inequivalent Co sites. In the first Co site, Co is bonded to one Tb, two equivalent Nd, and nine Co atoms to form a mixture of distorted corner, edge, and face-sharing CoTbNd2Co9 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.32–2.70 Å. In the second Co site, Co is bonded in a distorted single-bond geometry to one Tb, one Nd, seven Co, and one B atom. There are a spread of Co–Co bond distances ranging from 2.41–2.69 Å. The Co–B bond length is 2.03 Å. In the third Co site, Co is bonded in a distorted L-shaped geometry to two equivalent Tb, four Co, and two equivalent B atoms. Both Co–Co bond lengths are 2.69 Å. Both Co–B bond lengths are 2.01 Å. In the fourth Co site, Co is bonded in a 2-coordinate geometry to one Tb, one Nd, and twelve Co atoms. There are two shorter (2.56 Å) and two longer (2.59 Å) Co–Co bond lengths. In the fifth Co site, Co is bonded to two equivalent Tb, two equivalent Nd, and eight Co atoms to form a mixture of corner and face-sharing CoTb2Nd2Co8 cuboctahedra. All Co–Co bond lengths are 2.43 Å. In the sixth Co site, Co is bonded in a distorted q6 geometry to one Tb, one Nd, and ten Co atoms. There are two shorter (2.44 Å) and one longer (2.50 Å) Co–Co bond lengths. B is bonded in a 6-coordinate geometry to two equivalent Tb, one Nd, and six Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4HfAl15 by Materials Project

Tb4HfAl15 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded to twelve Al atoms to form TbAl12 cuboctahedra that share corners with six equivalent AlTb2Hf2Al8 cuboctahedra, corners with nine TbAl12 cuboctahedra, a faceface with one HfAl12 cuboctahedra, and faces with six TbAl12 cuboctahedra. There are a spread of Tb–Al bond distances ranging from 3.02–3.06 Å. In the second Tb site, Tb is bonded to twelve Al atoms to form TbAl12 cuboctahedra that share corners with twelve TbAl12 cuboctahedra, edges with six equivalent AlTb2Hf2Al8 cuboctahedra, faces with three equivalent TbAl12 cuboctahedra, faces with three equivalent HfAl12 cuboctahedra, and faces with three equivalent AlTb2Hf2Al8 cuboctahedra. There are a spread of Tb–Al bond distances ranging from 2.97–3.03 Å. Hf is bonded to twelve Al atoms to form HfAl12 cuboctahedra that share corners with six equivalent HfAl12 cuboctahedra, edges with six equivalent AlTb2Hf2Al8 cuboctahedra, faces with six equivalent AlTb2Hf2Al8 cuboctahedra, and faces with eight TbAl12 cuboctahedra. There are six shorter (2.99 Å) and six longer (3.03 Å) Hf–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded to two equivalent Tb, two equivalent Hf, and eight Al atoms to form distorted AlTb2Hf2Al8 cuboctahedra that share corners with four equivalent TbAl12 cuboctahedra, corners with six equivalent AlTb2Hf2Al8 cuboctahedra, edges with two equivalent HfAl12 cuboctahedra, edges with four equivalent TbAl12 cuboctahedra, edges with four equivalent AlTb2Hf2Al8 cuboctahedra, faces with two equivalent TbAl12 cuboctahedra, faces with two equivalent HfAl12 cuboctahedra, and faces with four equivalent AlTb2Hf2Al8 cuboctahedra. There are four shorter (2.86 Å) and four longer (3.03 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a distorted square co-planar geometry to four Tb and two equivalent Al atoms. Both Al–Al bond lengths are 3.00 Å. In the third Al site, Al is bonded in a 4-coordinate geometry to three Tb, one Hf, and six Al atoms. Both Al–Al bond lengths are 2.77 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3In5 by Materials Project

Tb3In5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 9-coordinate geometry to nine In atoms. There are a spread of Tb–In bond distances ranging from 3.10–3.53 Å. In the second Tb site, Tb is bonded in a 10-coordinate geometry to ten In atoms. There are a spread of Tb–In bond distances ranging from 3.21–3.49 Å. There are three inequivalent In sites. In the first In site, In is bonded in a 5-coordinate geometry to five Tb and six In atoms. There are a spread of In–In bond distances ranging from 3.12–3.37 Å. In the second In site, In is bonded in a 6-coordinate geometry to six Tb and four In atoms. There are two shorter (3.04 Å) and one longer (3.22 Å) In–In bond lengths. In the third In site, In is bonded in a 10-coordinate geometry to six Tb and four In atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5CuBi3 by Materials Project

Tb5CuBi3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to six equivalent Bi atoms. All Tb–Bi bond lengths are 3.32 Å. In the second Tb site, Tb is bonded to two equivalent Cu and five equivalent Bi atoms to form a mixture of distorted face, edge, and corner-sharing TbCu2Bi5 pentagonal bipyramids. Both Tb–Cu bond lengths are 2.88 Å. There are a spread of Tb–Bi bond distances ranging from 3.17–3.43 Å. Cu is bonded to six equivalent Tb atoms to form face-sharing CuTb6 octahedra. Bi is bonded in a 9-coordinate geometry to nine Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5Si3C by Materials Project

Tb5Si3C crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Tb+3.20+ sites. In the first Tb+3.20+ site, Tb+3.20+ is bonded to six equivalent Si4- atoms to form a mixture of distorted face, edge, and corner-sharing TbSi6 octahedra. The corner-sharing octahedral tilt angles are 29°. All Tb–Si bond lengths are 3.04 Å. In the second Tb+3.20+ site, Tb+3.20+ is bonded in a 2-coordinate geometry to five equivalent Si4- and two equivalent C4- atoms. There are a spread of Tb–Si bond distances ranging from 3.02–3.61 Å. Both Tb–C bond lengths are 2.50 Å. Si4- is bonded in a 9-coordinate geometry to nine Tb+3.20+ atoms. C4- is bonded to six equivalent Tb+3.20+ atoms to form face-sharing CTb6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Ga3(Fe7C)2 by Materials Project

Tb2Ga3(Fe7C)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Tb is bonded in a distorted bent 120 degrees geometry to six Fe, three Ga, and two equivalent C atoms. There are a spread of Tb–Fe bond distances ranging from 3.04–3.31 Å. There are two shorter (3.33 Å) and one longer (3.39 Å) Tb–Ga bond lengths. Both Tb–C bond lengths are 2.52 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 1-coordinate geometry to one Tb, ten Fe, and three Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.31–2.77 Å. All Fe–Ga bond lengths are 2.67 Å. In the second Fe site, Fe is bonded to three equivalent Tb, seven Fe, and two equivalent Ga atoms to form distorted FeTb3Ga2Fe7 cuboctahedra that share corners with four equivalent FeTb3Ga2Fe7 cuboctahedra, corners with five GaTb2Fe10 cuboctahedra, corners with four equivalent CTb2Fe4 octahedra, an edgeedge with one FeTb3Ga2Fe7 cuboctahedra, edges with three GaTb2Fe10 cuboctahedra, a faceface with one FeTb3Ga2Fe7 cuboctahedra, faces with three GaTb2Fe10 cuboctahedra, and faces with two equivalent CTb2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.51–2.63 Å. Both Fe–Ga bond lengths are 2.51 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe, two Ga, and one C atom. The Fe–Fe bond length is 2.63 Å. There are one shorter (2.51 Å) and one longer (2.52 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.90 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Tb, eight Fe, and two equivalent Ga atoms. Both Fe–Fe bond lengths are 2.50 Å. Both Fe–Ga bond lengths are 2.47 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to four Fe, two Ga, and one C atom. There are one shorter (2.45 Å) and one longer (2.46 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.86 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to two equivalent Tb and ten Fe atoms to form distorted GaTb2Fe10 cuboctahedra that share corners with four equivalent GaTb2Fe10 cuboctahedra, corners with six equivalent FeTb3Ga2Fe7 cuboctahedra, edges with two equivalent FeTb3Ga2Fe7 cuboctahedra, faces with two equivalent FeTb3Ga2Fe7 cuboctahedra, faces with four equivalent GaTb2Fe10 cuboctahedra, and faces with four equivalent CTb2Fe4 octahedra. In the second Ga site, Ga is bonded to two equivalent Tb and ten Fe atoms to form distorted GaTb2Fe10 cuboctahedra that share corners with two equivalent FeTb3Ga2Fe7 cuboctahedra, corners with four GaTb2Fe10 cuboctahedra, corners with two equivalent CTb2Fe4 octahedra, edges with two equivalent FeTb3Ga2Fe7 cuboctahedra, faces with two equivalent FeTb3Ga2Fe7 cuboctahedra, faces with four GaTb2Fe10 cuboctahedra, and faces with two equivalent CTb2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. C is bonded to two equivalent Tb and four Fe atoms to form CTb2Fe4 octahedra that share corners with two equivalent GaTb2Fe10 cuboctahedra, corners with four equivalent FeTb3Ga2Fe7 cuboctahedra, corners with two equivalent CTb2Fe4 octahedra, faces with two equivalent FeTb3Ga2Fe7 cuboctahedra, and faces with four GaTb2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 62°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbCo3 by Materials Project

TbCo3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 12-coordinate geometry to twelve Co atoms. There are a spread of Tb–Co bond distances ranging from 2.87–3.10 Å. In the second Tb site, Tb is bonded in a 6-coordinate geometry to eighteen Co atoms. There are six shorter (2.87 Å) and twelve longer (3.18 Å) Tb–Co bond lengths. There are three inequivalent Co sites. In the first Co site, Co is bonded to five Tb and seven Co atoms to form a mixture of edge, face, and corner-sharing CoTb5Co7 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.42–2.55 Å. In the second Co site, Co is bonded in a 12-coordinate geometry to three equivalent Tb and six equivalent Co atoms. In the third Co site, Co is bonded to six equivalent Tb and six equivalent Co atoms to form CoTb6Co6 cuboctahedra that share corners with twelve equivalent CoTb5Co7 cuboctahedra, edges with six equivalent CoTb6Co6 cuboctahedra, and faces with eighteen equivalent CoTb5Co7 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiTb5Sn3 by Materials Project

LiTb5Sn3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. Li is bonded to six equivalent Tb atoms to form face-sharing LiTb6 octahedra. All Li–Tb bond lengths are 3.05 Å. There are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to six equivalent Sn atoms. All Tb–Sn bond lengths are 3.34 Å. In the second Tb site, Tb is bonded in a 7-coordinate geometry to two equivalent Li and five equivalent Sn atoms. There are a spread of Tb–Sn bond distances ranging from 3.13–3.45 Å. Sn is bonded in a 9-coordinate geometry to nine Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3Ge4 by Materials Project

Tb3Ge4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 8-coordinate geometry to eight Ge atoms. There are a spread of Tb–Ge bond distances ranging from 2.99–3.11 Å. In the second Tb site, Tb is bonded in a 5-coordinate geometry to seven Ge atoms. There are a spread of Tb–Ge bond distances ranging from 2.93–3.19 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six Tb and three Ge atoms. There are one shorter (2.62 Å) and two longer (2.88 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 9-coordinate geometry to seven Tb and two equivalent Ge atoms. In the third Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Tb and four equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Cl3 by Materials Project

Tb2Cl3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 4-coordinate geometry to five Cl atoms. There are a spread of Tb–Cl bond distances ranging from 2.77–3.37 Å. In the second Tb site, Tb is bonded in a pentagonal planar geometry to five Cl atoms. There are a spread of Tb–Cl bond distances ranging from 2.73–2.85 Å. There are three inequivalent Cl sites. In the first Cl site, Cl is bonded in a trigonal non-coplanar geometry to three equivalent Tb atoms. In the second Cl site, Cl is bonded in a distorted rectangular see-saw-like geometry to four Tb atoms. In the third Cl site, Cl is bonded in a distorted T-shaped geometry to three Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5CuPb3 by Materials Project

Tb5CuPb3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded to two equivalent Cu and five equivalent Pb atoms to form a mixture of distorted corner, edge, and face-sharing TbCu2Pb5 pentagonal bipyramids. Both Tb–Cu bond lengths are 2.88 Å. There are a spread of Tb–Pb bond distances ranging from 3.17–3.57 Å. In the second Tb site, Tb is bonded in a 6-coordinate geometry to six equivalent Pb atoms. All Tb–Pb bond lengths are 3.30 Å. Cu is bonded to six equivalent Tb atoms to form face-sharing CuTb6 octahedra. Pb is bonded in a 9-coordinate geometry to nine Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5(SiB4)2 by Materials Project

Tb5Si2B8 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional and consists of four silicon molecules and one Tb5B8 framework. In the Tb5B8 framework, there are two inequivalent Tb+3.20+ sites. In the first Tb+3.20+ site, Tb+3.20+ is bonded in a 9-coordinate geometry to nine B3- atoms. There are a spread of Tb–B bond distances ranging from 2.65–2.98 Å. In the second Tb+3.20+ site, Tb+3.20+ is bonded in a linear geometry to two equivalent B3- atoms. Both Tb–B bond lengths are 2.76 Å. There are three inequivalent B3- sites. In the first B3- site, B3- is bonded in a 9-coordinate geometry to four equivalent Tb+3.20+ and five B3- atoms. There are a spread of B–B bond distances ranging from 1.76–1.84 Å. In the second B3- site, B3- is bonded in a 3-coordinate geometry to six equivalent Tb+3.20+ and three B3- atoms. The B–B bond length is 1.85 Å. In the third B3- site, B3- is bonded in a 9-coordinate geometry to five Tb+3.20+ and four equivalent B3- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5Ge3B by Materials Project

Tb5BGe3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to six equivalent Ge atoms. All Tb–Ge bond lengths are 3.10 Å. In the second Tb site, Tb is bonded in a 7-coordinate geometry to two equivalent B and five equivalent Ge atoms. Both Tb–B bond lengths are 2.61 Å. There are a spread of Tb–Ge bond distances ranging from 3.01–3.49 Å. B is bonded to six equivalent Tb atoms to form face-sharing BTb6 octahedra. Ge is bonded in a 9-coordinate geometry to nine Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4ZrAl15 by Materials Project

Tb4ZrAl15 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded to twelve Al atoms to form TbAl12 cuboctahedra that share corners with six equivalent AlTb2Zr2Al8 cuboctahedra, corners with nine TbAl12 cuboctahedra, a faceface with one ZrAl12 cuboctahedra, and faces with six TbAl12 cuboctahedra. There are a spread of Tb–Al bond distances ranging from 3.02–3.06 Å. In the second Tb site, Tb is bonded to twelve Al atoms to form TbAl12 cuboctahedra that share corners with twelve TbAl12 cuboctahedra, edges with six equivalent AlTb2Zr2Al8 cuboctahedra, faces with three equivalent TbAl12 cuboctahedra, faces with three equivalent ZrAl12 cuboctahedra, and faces with three equivalent AlTb2Zr2Al8 cuboctahedra. There are a spread of Tb–Al bond distances ranging from 2.97–3.04 Å. Zr is bonded to twelve Al atoms to form ZrAl12 cuboctahedra that share corners with six equivalent ZrAl12 cuboctahedra, edges with six equivalent AlTb2Zr2Al8 cuboctahedra, faces with six equivalent AlTb2Zr2Al8 cuboctahedra, and faces with eight TbAl12 cuboctahedra. There are six shorter (3.01 Å) and six longer (3.03 Å) Zr–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded to two equivalent Tb, two equivalent Zr, and eight Al atoms to form distorted AlTb2Zr2Al8 cuboctahedra that share corners with four equivalent TbAl12 cuboctahedra, corners with six equivalent AlTb2Zr2Al8 cuboctahedra, edges with two equivalent ZrAl12 cuboctahedra, edges with four equivalent TbAl12 cuboctahedra, edges with four equivalent AlTb2Zr2Al8 cuboctahedra, faces with two equivalent TbAl12 cuboctahedra, faces with two equivalent ZrAl12 cuboctahedra, and faces with four equivalent AlTb2Zr2Al8 cuboctahedra. There are four shorter (2.87 Å) and four longer (3.03 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a distorted square co-planar geometry to four Tb and two equivalent Al atoms. Both Al–Al bond lengths are 3.00 Å. In the third Al site, Al is bonded in a 10-coordinate geometry to three Tb, one Zr, and six Al atoms. Both Al–Al bond lengths are 2.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Ga8Fe by Materials Project

Tb2FeGa8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Tb is bonded to twelve Ga atoms to form a mixture of corner and face-sharing TbGa12 cuboctahedra. There are a spread of Tb–Ga bond distances ranging from 3.00–3.06 Å. Fe is bonded in a body-centered cubic geometry to eight Ga atoms. All Fe–Ga bond lengths are 2.48 Å. There are six inequivalent Ga sites. In the first Ga site, Ga is bonded in a 11-coordinate geometry to two equivalent Tb, two equivalent Fe, and seven Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.54–3.02 Å. In the second Ga site, Ga is bonded in a 11-coordinate geometry to two equivalent Tb, two equivalent Fe, and seven Ga atoms. There are one shorter (2.54 Å) and two longer (2.99 Å) Ga–Ga bond lengths. In the third Ga site, Ga is bonded in a 11-coordinate geometry to two equivalent Tb, two equivalent Fe, and seven Ga atoms. Both Ga–Tb bond lengths are 3.00 Å. There are two shorter (2.99 Å) and four longer (3.02 Å) Ga–Ga bond lengths. In the fourth Ga site, Ga is bonded in a 11-coordinate geometry to two equivalent Tb, two equivalent Fe, and seven Ga atoms. Both Ga–Tb bond lengths are 3.00 Å. Both Ga–Ga bond lengths are 2.99 Å. In the fifth Ga site, Ga is bonded in a distorted square co-planar geometry to four equivalent Tb atoms. In the sixth Ga site, Ga is bonded in a distorted rectangular see-saw-like geometry to four equivalent Tb and four Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4Co3 by Materials Project

Tb4Co3 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 7-coordinate geometry to seven Co atoms. There are a spread of Tb–Co bond distances ranging from 2.87–3.02 Å. In the second Tb site, Tb is bonded in a 4-coordinate geometry to four Co atoms. There are a spread of Tb–Co bond distances ranging from 2.79–3.07 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded in a 9-coordinate geometry to six equivalent Tb and three equivalent Co atoms. All Co–Co bond lengths are 2.34 Å. In the second Co site, Co is bonded in a 9-coordinate geometry to eight Tb and one Co atom. In the third Co site, Co is bonded in a 6-coordinate geometry to six equivalent Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4MgGe4 by Materials Project

MgTb4Ge4 is Magnesium tetraboride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Mg is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Mg–Ge bond distances ranging from 2.77–3.17 Å. There are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Tb–Ge bond distances ranging from 2.87–3.07 Å. In the second Tb site, Tb is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Tb–Ge bond distances ranging from 3.00–3.36 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Mg, six Tb, and one Ge atom. The Ge–Ge bond length is 2.60 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to one Mg, six Tb, and one Ge atom. In the third Ge site, Ge is bonded in a 9-coordinate geometry to one Mg, seven Tb, and one Ge atom. The Ge–Ge bond length is 2.72 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Temperature-induced valence-state transition in double perovskite Ba 2 - x Sr x TbIrO 6

In this paper, a temperature-induced valence-state transition is studied in a narrow composition range 0.2 ≤ x ≤ 0.375 of Ba 2 - x Sr x TbIrO 6 by means of x-ray and neutron powder diffraction, resonant inelastic x-ray scattering, magnetic susceptibility, electrical resistivity, and specific heat measurements. The valence-state transition involves an electron transfer between Tb and Ir leading to the valence-state change between Tb 3 + / Ir 5 + and Tb 4 + / Ir 4 + phases. This first-order transition has a dramatic effect on the lattice, transport properties, and the long-range magnetic order at low temperatures for both Tb and Ir ions. Ir 5 + ion has an electronic configuration of 5 d 4 ( J eff = 0 ), which is expected to be nonmagnetic. In contrast, Ir 4 + ion with a configuration of 5 d 5 ( J eff = 1/2) favors a long-range magnetic order. For x = 0.1 with Tb 3 + / Ir 5 + configuration to the lowest temperature (2 K) investigated in this paper, a spin-glass behavior is observed around 5 K indicating Ir 5 + ( J eff = 0 ) ions act as a spacer reducing the magnetic interactions between Tb 3 + ions. For x = 0.5 with Tb 4 + / Ir 4 + configuration below the highest temperature 400 K of this paper, a long-range antiferromagnetic order at T N = 40 K is observed highlighting the importance of Ir 4 + ( J eff = 1/2) ions in promoting the long-range magnetic order of both Tb and Ir ions. For 0.2 ≤ x ≤ 0.375, a temperature-induced valence-state transition from high-temperature Tb 3 + / Ir 5 + phase to low-temperature Tb 4 + / Ir 4 + phase occurs in the temperature range 180 K ≤ T ≤ 325 K and the transition temperature increases with x . The compositional dependence demonstrates the ability to tune the the valence state for a critical region of x that leads to a concurrent change in magnetism and structure. Furthermore, this tuning ability could be employed with suitable strain in thin films to act as a switch as the magnetism is manipulated.

36 MATERIALS SCIENCE↗