Materials Data on Cs2Tc2O5 by Materials Project

Abstract

Cs2Tc2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. All Cs–O bond lengths are 3.14 Å. In the second Cs1+ site, Cs1+ is bonded to twelve O2- atoms to form CsO12 cuboctahedra that share corners with four equivalent CsO12 cuboctahedra, faces with four equivalent CsO12 cuboctahedra, and faces with eight equivalent TcO5 square pyramids. There are four shorter (2.79 Å) and eight longer (3.00 Å) Cs–O bond lengths. Tc4+ is bonded to five O2- atoms to form TcO5 square pyramids that share corners with five equivalent TcO5 square pyramids and faces with four equivalent CsO12 cuboctahedra. There are four shorter (1.98 Å) and one longer (2.06 Å) Tc–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Cs1+ and two equivalent Tc4+ atoms. In the second O2- site, O2- is bonded to four equivalent Cs1+ and two equivalent Tc4+ atoms to form a mixture of corner and edge-sharing OCs4Tc2 octahedra. The corner-sharing octahedral tilt angles are 0°.