Materials Data on Sr2TcO4 by Materials Project

Abstract

Sr2TcO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are one shorter (2.45 Å) and eight longer (2.76 Å) Sr–O bond lengths. Tc4+ is bonded to six O2- atoms to form corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.94 Å) and two longer (2.14 Å) Tc–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to five equivalent Sr2+ and one Tc4+ atom to form a mixture of edge and corner-sharing OSr5Tc octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two equivalent Tc4+ atoms.