Materials Data on Na3Mn2(GeO4)3 by Materials Project
Na3Mn2(GeO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.40 Å) and four longer (2.53 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.53 Å. There are two inequivalent Mn+4.50+ sites. In the first Mn+4.50+ site, Mn+4.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent GeO4 tetrahedra. All Mn–O bond lengths are 1.94 Å. In the second Mn+4.50+ site, Mn+4.50+ is bonded to six equivalent O2- atoms to form MnO6 octahedra that share corners with six equivalent GeO4 tetrahedra. All Mn–O bond lengths are 1.94 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four MnO6 octahedra. The corner-sharing octahedral tilt angles are 46°. All Ge–O bond lengths are 1.78 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Mn+4.50+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Mn+4.50+, and one Ge4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Mn+4.50+, and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Mn+4.50+, and one Ge4+ atom.