Materials Data on Ca2GeN2 by Materials Project
Ca2GeN2 crystallizes in the tetragonal P4_2/mbc space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to five N3- atoms to form a mixture of edge and corner-sharing CaN5 trigonal bipyramids. There are a spread of Ca–N bond distances ranging from 2.40–2.61 Å. In the second Ca2+ site, Ca2+ is bonded to five N3- atoms to form a mixture of edge and corner-sharing CaN5 square pyramids. There are a spread of Ca–N bond distances ranging from 2.42–2.59 Å. Ge2+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.87 Å) and one longer (1.90 Å) Ge–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to five Ca2+ and one Ge2+ atom to form a mixture of distorted edge and corner-sharing NCa5Ge octahedra. The corner-sharing octahedra tilt angles range from 7–60°. In the second N3- site, N3- is bonded to five Ca2+ and one Ge2+ atom to form a mixture of edge and corner-sharing NCa5Ge octahedra. The corner-sharing octahedra tilt angles range from 7–60°.