DOI: 10.17188/1287349
title: Materials Data on Na4GeH28(Se2O7)2 by Materials Project

description: (Na2(H2O)7)2GeSe4 crystallizes in the monoclinic C2 space group. The structure is two-dimensional and consists of two GeSe4 clusters and one Na2(H2O)7 sheet oriented in the (0, 0, 1) direction. In each GeSe4 cluster, Ge4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are two shorter (2.38 Å) and two longer (2.40 Å) Ge–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted single-bond geometry to one Ge4+ atom. In the second Se2- site, Se2- is bonded in a single-bond geometry to one Ge4+ atom. In the Na2(H2O)7 sheet, there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of corner, edge, and face-sharing NaO6 octahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Na–O bond distances ranging from 2.38–2.45 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of corner and face-sharing NaO6 octahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Na–O bond distances ranging from 2.41–2.48 Å. There are fourteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one Na1+ and two H1+ atoms. In the second O2- site, O2- is bonded in a water-like geometry to one Na1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms.