Materials Data on CaCO3 by Materials Project

Abstract

CaCO3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.43–2.69 Å. 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. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ca2+ and one C4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ca2+ and one C4+ atom.