Interatomic potentials for CaCO3 polymorphs (calcite and aragonite), fitted to elastic and vibrational data

Abstract

Abstract. Calcite and aragonite have been modeled using rigid-ion, two-body Born-type potentials, supplemented by O-C-O angular terms inside the CO3 groups. A shell model has also been developed for calcite. Atomic charges, repulsive parameters and force constants have been optimized to reproduce the equilibrium crystal structures, the elastic constants and the Raman and infrared vibrational frequencies. The rigid-ion potential RIM (atomic charges: Zo = -0.995 e, Zc = 0.985 e, Zc, = 2.0 e) fitted to calcite properties is able to account for those of aragonite as well. Experimental unit-cell edges, elastic constants, internal and lattice frequencies are reproduced with average relative errors of 2.1, 5.5, 2.4, 15.1% for calcite and of 0.2, 19.4, 2.5, 11.8 % for aragonite, respectively. The RIM potential is suitable for thermodynamic and phase diagram simulations in the CaCO3 system, and is discussed and compared to other potentials.

A molecular dynamics investigation into the adsorption behavior inside {001} kaolinite and {1014} calcite nano-scale channels: the case with confined hydrocarbon liquid, acid gases, and water

“…Neutral octahedral {001} surface of kaolinite was used, as well. To model calcite surfaces, rigid ion model of a force field presented by Pavese et al (1992Pavese et al ( , 1996 was employed. The CLAYFF force field (Cygan et al 2004) was adopted to define all bonded and non-bonded interaction parameters of kaolinite surface.…”

How does an amorphous surface influence molecular binding? – ovocleidin-17 and amorphous calcium carbonate

“…The forcefield description of OC-17 was that of the general united atom AM-BER model 21 * and the structure was taken from ref. 14 , while the calcium carbonate was described with the rigid ion nonpolarisable potentials of Pavese et al 22,23 and the water was modelled as TIP3P 24 . Newer forcefields have been developed for modelling calcium carbonate e.g.…”

Growth modification of seeded calcite using carboxylic acids: Atomistic simulations

“…In this model the oxygen is split into two particles attached to each other by a harmonic spring potential and carrying together the overall charge of the ion. Pavese et al first derived the calcite potential parameters used in this study [30][31] which have since been successfully applied to the accurate representations of calcite surfaces [32][33][34][35][36][37]. These potentials were used to construct flat and stepped surfaces starting from the crystallographic calcite unit-cell using the computer code METADISE [38].…”