Materials Data on Na2TiGeO5 by Materials Project
Na2TiGeO5 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with four equivalent GeO4 tetrahedra, and edges with four equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are four shorter (2.33 Å) and two longer (2.70 Å) Na–O bond lengths. Ti4+ is bonded in a 5-coordinate geometry to five O2- atoms. There is one shorter (1.72 Å) and four longer (2.01 Å) Ti–O bond length. Ge4+ is bonded to four equivalent O2- atoms to form GeO4 tetrahedra that share corners with eight equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 62°. All Ge–O bond lengths are 1.77 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na1+, one Ti4+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to four equivalent Na1+ and one Ti4+ atom.