Materials Data on GeTe4Pb3 by Materials Project
(PbTe)3GeTe is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to six Te2- atoms to form PbTe6 octahedra that share corners with six equivalent PbTe6 octahedra, edges with four equivalent GeTe6 octahedra, and edges with eight PbTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Pb–Te bond distances ranging from 3.19–3.27 Å. In the second Pb2+ site, Pb2+ is bonded to six Te2- atoms to form PbTe6 octahedra that share corners with two equivalent GeTe6 octahedra, corners with four equivalent PbTe6 octahedra, and edges with twelve PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.23 Å) and two longer (3.39 Å) Pb–Te bond lengths. Ge2+ is bonded to six Te2- atoms to form GeTe6 octahedra that share corners with two equivalent PbTe6 octahedra, corners with four equivalent GeTe6 octahedra, edges with four equivalent GeTe6 octahedra, and edges with eight equivalent PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (3.07 Å) and four longer (3.23 Å) Ge–Te bond lengths. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to five Pb2+ and one Ge2+ atom to form a mixture of edge and corner-sharing TeGePb5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second Te2- site, Te2- is bonded to two equivalent Pb2+ and four equivalent Ge2+ atoms to form TeGe4Pb2 octahedra that share corners with six TeGe4Pb2 octahedra and edges with twelve TeGePb5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third Te2- site, Te2- is bonded to six Pb2+ atoms to form TePb6 octahedra that share corners with six TeGe4Pb2 octahedra and edges with twelve TeGePb5 octahedra. The corner-sharing octahedral tilt angles are 0°.