Materials Data on Ca3Mg2(AsO4)3 by Materials Project
Ca3Mg2(AsO4)3 crystallizes in the cubic Ia-3d space group. The structure is three-dimensional. Ca is bonded in a distorted body-centered cubic geometry to eight equivalent O atoms. There are four shorter (2.43 Å) and four longer (2.56 Å) Ca–O bond lengths. Mg is bonded to six equivalent O atoms to form MgO6 octahedra that share corners with six equivalent AsO4 tetrahedra. All Mg–O bond lengths are 2.12 Å. As is bonded to four equivalent O atoms to form AsO4 tetrahedra that share corners with four equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 50°. All As–O bond lengths are 1.77 Å. O is bonded to two equivalent Ca, one Mg, and one As atom to form a mixture of distorted edge and corner-sharing OCa2MgAs trigonal pyramids.