Materials Data on CaCO3 by Materials Project

Abstract

CaCO3 is Calcite-like structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form corner-sharing CaO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.34–2.46 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing CaO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 48–67°. There are a spread of Ca–O bond distances ranging from 2.34–2.43 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.30 Å) C–O bond length. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. All C–O bond lengths are 1.30 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one C4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one C4+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Ca2+ and one C4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one C4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one C4+ atom.