Materials Data on Na2Ge2O5 by Materials Project

Abstract

Na2Ge2O5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share corners with four GeO4 tetrahedra, corners with four NaO5 trigonal bipyramids, an edgeedge with one GeO4 tetrahedra, and edges with four NaO5 trigonal bipyramids. There are a spread of Na–O bond distances ranging from 2.39–2.70 Å. In the second Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share corners with four GeO4 tetrahedra, corners with four NaO5 trigonal bipyramids, an edgeedge with one GeO4 tetrahedra, and edges with four NaO5 trigonal bipyramids. There are a spread of Na–O bond distances ranging from 2.39–2.71 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three equivalent GeO4 tetrahedra, corners with four NaO5 trigonal bipyramids, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Ge–O bond distances ranging from 1.73–1.80 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three equivalent GeO4 tetrahedra, corners with four NaO5 trigonal bipyramids, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Ge–O bond distances ranging from 1.72–1.81 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two Ge4+ atoms. In the second O2- site, O2- is bonded to four Na1+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing ONa4Ge trigonal bipyramids. In the third O2- site, O2- is bonded to four Na1+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing ONa4Ge trigonal bipyramids. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two Ge4+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ge4+ atoms.