Materials Data on Hf(MoO4)2 by Materials Project
HfMo2O8 crystallizes in the trigonal P-31c space group. The structure is two-dimensional and consists of two HfMo2O8 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six equivalent MoO4 tetrahedra. All Hf–O bond lengths are 2.07 Å. In the second Hf4+ site, Hf4+ is bonded to six equivalent O2- atoms to form HfO6 octahedra that share corners with six equivalent MoO4 tetrahedra. All Hf–O bond lengths are 2.08 Å. Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with three HfO6 octahedra. The corner-sharing octahedra tilt angles range from 9–23°. There are a spread of Mo–O bond distances ranging from 1.73–1.82 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one Mo6+ atom. In the second O2- site, O2- is bonded in a linear geometry to one Hf4+ and one Mo6+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to one Hf4+ and one Mo6+ atom.