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DOE OSTI · 1745943

Materials Data on Ti2CoNi by Materials Project

Abstract

TiNi(TiCo) crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are six inequivalent Ti sites. In the first Ti site, Ti is bonded in a 2-coordinate geometry to four equivalent Ti, four Co, and two equivalent Ni atoms. All Ti–Ti bond lengths are 2.84 Å. There are two shorter (2.70 Å) and two longer (2.71 Å) Ti–Co bond lengths. Both Ti–Ni bond lengths are 2.56 Å. In the second Ti site, Ti is bonded in a 2-coordinate geometry to four equivalent Ti, two equivalent Co, and four Ni atoms. All Ti–Ti bond lengths are 2.86 Å. Both Ti–Co bond lengths are 2.73 Å. There are two shorter (2.55 Å) and two longer (2.68 Å) Ti–Ni bond lengths. In the third Ti site, Ti is bonded in a 2-coordinate geometry to two equivalent Ti, three Co, and three Ni atoms. There are one shorter (2.83 Å) and one longer (2.85 Å) Ti–Ti bond lengths. There are a spread of Ti–Co bond distances ranging from 2.69–2.73 Å. There are a spread of Ti–Ni bond distances ranging from 2.55–2.70 Å. In the fourth Ti site, Ti is bonded in a 2-coordinate geometry to four equivalent Ti, two equivalent Co, and four Ni atoms. All Ti–Ti bond lengths are 3.05 Å. Both Ti–Co bond lengths are 2.75 Å. There are two shorter (2.57 Å) and two longer (2.71 Å) Ti–Ni bond lengths. In the fifth Ti site, Ti is bonded in a 2-coordinate geometry to four equivalent Ti, four Co, and two equivalent Ni atoms. All Ti–Ti bond lengths are 3.02 Å. There are two shorter (2.55 Å) and two longer (2.73 Å) Ti–Co bond lengths. Both Ti–Ni bond lengths are 2.72 Å. In the sixth Ti site, Ti is bonded in a 2-coordinate geometry to eight Ti, three Co, and three Ni atoms. There are one shorter (3.01 Å) and one longer (3.06 Å) Ti–Ti bond lengths. There are a spread of Ti–Co bond distances ranging from 2.53–2.76 Å. There are one shorter (2.59 Å) and two longer (2.72 Å) Ti–Ni bond lengths. There are three inequivalent Co sites. In the first Co site, Co is bonded to six Ti, one Co, and five Ni atoms to form face-sharing CoTi6CoNi5 cuboctahedra. The Co–Co bond length is 2.37 Å. There are two shorter (2.37 Å) and three longer (2.39 Å) Co–Ni bond lengths. In the second Co site, Co is bonded to six Ti, two equivalent Co, and four Ni atoms to form face-sharing CoTi6Co2Ni4 cuboctahedra. Both Co–Co bond lengths are 2.38 Å. There are two shorter (2.38 Å) and two longer (2.39 Å) Co–Ni bond lengths. In the third Co site, Co is bonded in a 12-coordinate geometry to six Ti, four Co, and two equivalent Ni atoms. The Co–Co bond length is 2.67 Å. Both Co–Ni bond lengths are 2.65 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to six Ti, five Co, and one Ni atom. The Ni–Ni bond length is 2.63 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to six Ti, three Co, and two equivalent Ni atoms. Both Ni–Ni bond lengths are 2.67 Å. In the third Ni site, Ni is bonded in a 12-coordinate geometry to six Ti, three Co, and three Ni atoms. The Ni–Ni bond length is 2.65 Å.

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2020-04-30. Materials Data on Ti2CoNi by Materials Project. https://doi.org/10.17188/1745943

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36 MATERIALS SCIENCE↗