DOE OSTI2020
FeAgTe2 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded in a 4-coordinate geometry to two equivalent Ag1+ and four Te2- atoms. Both Fe–Ag bond lengths are 2.78 Å. There are a spread of Fe–Te bond distances ranging from 2.57–2.77 Å. In the second Fe3+ site, Fe3+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of Fe–Te bond distances ranging from 2.54–3.04 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to six Te2- atoms to form a mixture of distorted corner and edge-sharing AgTe6 octahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Ag–Te bond distances ranging from 2.85–3.08 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to two equivalent Fe3+ and three equivalent Te2- atoms. There are one shorter (2.70 Å) and two longer (2.76 Å) Ag–Te bond lengths. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 4-coordinate geometry to three Fe3+ and one Ag1+ atom. In the second Te2- site, Te2- is bonded in a 2-coordinate geometry to three Fe3+ and two equivalent Ag1+ atoms. In the third Te2- site, Te2- is bonded in a 5-coordinate geometry to two Fe3+ and three equivalent Ag1+ atoms. In the fourth Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Fe3+ and three equivalent Ag1+ atoms.