Materials Data on Nd4Si2Se3O7 by Materials Project
Nd4Si2Se3O7 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. there are two inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 9-coordinate geometry to three Se2- and six O2- atoms. There are one shorter (2.97 Å) and two longer (3.02 Å) Nd–Se bond lengths. There are a spread of Nd–O bond distances ranging from 2.52–2.67 Å. In the second Nd3+ site, Nd3+ is bonded in a 6-coordinate geometry to three Se2- and three O2- atoms. There are one shorter (2.98 Å) and two longer (3.01 Å) Nd–Se bond lengths. There are one shorter (2.40 Å) and two longer (2.51 Å) Nd–O bond lengths. Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted square co-planar geometry to four equivalent Nd3+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to four equivalent Nd3+ and two equivalent O2- atoms. Both Se–O bond lengths are 3.41 Å. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to four Nd3+ atoms. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Si4+ and one Se2- atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Nd3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Nd3+ and one Si4+ atom.