DOI: 10.17188/1283338
title: Materials Data on Sr2IrO4 by Materials Project

description: Sr2IrO4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share a cornercorner with one OSr4O trigonal bipyramid and an edgeedge with one SrO7 pentagonal bipyramid. There are a spread of Sr–O bond distances ranging from 2.46–2.72 Å. In the second Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.45–2.67 Å. In the third Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–3.20 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–2.97 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.85 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.38–2.87 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.82 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.09 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–3.07 Å. In the tenth Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share a cornercorner with one OSr4O trigonal bipyramid and an edgeedge with one SrO6 pentagonal pyramid. There are a spread of Sr–O bond distances ranging from 2.41–2.80 Å. In the eleventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.37–2.77 Å. In the twelfth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.92 Å. In the thirteenth Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.52 Å. In the fourteenth Sr2+ site, Sr2+ is bonded in a distorted pentagonal bipyramidal geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.39–2.80 Å. In the fifteenth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.32–2.88 Å. In the sixteenth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.38–2.74 Å. There are eight inequivalent Ir4+ sites. In the first Ir4+ site, Ir4+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Ir–O bond distances ranging from 1.83–2.02 Å. In the second Ir4+ site, Ir4+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Ir–O bond distances ranging from 1.90–2.02 Å. In the third Ir4+ site, Ir4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.86 Å) and one longer (1.92 Å) Ir–O bond length. In the fourth Ir4+ site, Ir4+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Ir–O bond distances ranging from 1.90–1.99 Å. In the fifth Ir4+ site, Ir4+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Ir–O bond distances ranging from 1.89–2.08 Å. In the sixth Ir4+ site, Ir4+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Ir–O bond distances ranging from 1.95–2.13 Å. In the seventh Ir4+ site, Ir4+ is bonded in a T-shaped geometry to three O2- atoms. There are a spread of Ir–O bond distances ranging from 1.81–2.00 Å. In the eighth Ir4+ site, Ir4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.84 Å) and one longer (1.93 Å) Ir–O bond length. There are thirty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two Ir4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one O2- atom. The O–O bond length is 1.49 Å. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ir4+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Sr2+ and two Ir4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Ir4+ atom. In the sixth O2- site, O2- is bonded to four Sr2+ atoms to form distorted OSr4 trigonal pyramids that share a cornercorner with one OSr4O trigonal bipyramid and an edgeedge with one OSr3Ir tetrahedra. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one O2- atom. The O–O bond length is 1.51 Å. In the eighth O2- site, O2- is bonded to three Sr2+ and one Ir4+ atom to form distorted OSr3Ir trigonal pyramids that share a cornercorner with one OSr4O trigonal bipyramid, an edgeedge with one OSr3Ir tetrahedra, and an edgeedge with one OSr3Ir trigonal pyramid. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ir4+ atom. In the tenth O2- site, O2- is bonded to three Sr2+ and one Ir4+ atom to form distorted OSr3Ir tetrahedra that share a cornercorner with one OSr3Ir tetrahedra, corners with two equivalent OSr4O trigonal bipyramids, and an edgeedge with one OSr4 trigonal pyramid. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Sr2+ and one Ir4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and two Ir4+ atoms. In the thirteenth O2- site, O2- is bonded to three Sr2+ and one Ir4+ atom to form distorted OSr3Ir tetrahedra that share a cornercorner with one OSr3Ir tetrahedra, a cornercorner with one OSr4O trigonal bipyramid, a cornercorner with one OSr3Ir trigonal pyramid, and an edgeedge with one OSr3Ir trigonal pyramid. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one O2- atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one O2- atom. The O–O bond length is 1.50 Å. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one Ir4+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one O2- atom. In the eighteenth O2- site, O2- is bonded to four Sr2+ and one O2- atom to form distorted OSr4O trigonal bipyramids that share a cornercorner with one SrO7 pentagonal bipyramid, a cornercorner with one SrO6 pentagonal pyramid, corners with three OSr3Ir tetrahedra, and corners with three OSr3Ir trigonal pyramids. The O–O bond length is 1.51 Å. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one O2- atom. The O–O bond length is 1.50 Å. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+ and one Ir4+ atom. In the twenty-first O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one O2- atom. In the twenty-second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Sr2+ and one Ir4+ atom. In the twenty-third O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Ir4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 5-coordinate geometry to five Sr2+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ir4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one O2- atom. In the twenty-seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one Ir4+ atom. In the twenty-eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Ir4+ atoms. In the twenty-ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Ir4+ atom. In the thirtieth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Sr2+ and one O2- atom. In the thirty-first O2- site, O2- is bonded to three Sr2+ and one Ir4+ atom to form OSr3Ir trigonal pyramids that share a cornercorner with one OSr3Ir tetrahedra, a cornercorner with one OSr4O trigonal bipyramid, and an edgeedge with one OSr3Ir trigonal pyramid. In the thirty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ir4+ atom.