Bulk and surface properties of gypsum: A comparison between classical force fields and dispersion-corrected DFT calculations

Adsorption and solidification of cadmium by calcium sulfate dihydrate (gypsum) in an aqueous environment: a dispersion-corrected DFT and ab initio molecular dynamics study

“…44 Moreover, it can be seen that the deviation between our calculation result of gypsum crystal lattice parameters using the TS scheme (DFT-D TS ) and the experimental value is less than 1%. The calculation result in this manuscript is very close to the experimental value and the calculation result of Khalkhali et al, 39 indicating that it is appropriate to use the DFT-D TS method for studying gypsum in this manuscript. The TS scheme uses the same damping function as the Grimme (2006) scheme 45 but following Jurecka et al (2007) 46 instead scales the combined the vdW radius by a XC-functional dependent factor SR a 1 (s6 R1), thereby correcting where the XC-functional influence is strongest and leaving asymptotics intact.…”

“…where E slab and E bulk are the total energies of the surface slab and the bulk unit cell, respectively; N slab and N bulk are a Experimental values were taken from the X-ray diffraction study of Comodi et al 43 The calculation results obtained by using DFT without dispersion correction, DFT-D TS and DFT-D2 were taken from the study of Khalkhali et al 39 PCCP Paper the numbers of atoms contained in the slab and the bulk unit cell, respectively; A is the unit area of the surface; 2 denotes two surfaces along the z-axis in the surface slab.…”

“…37,38 The (010) plane is one of the major exposure facets of a gypsum crystal and has a low surface energy, so it is often used as an object to study the adsorption of the gypsum surface. 38,39 Besides, the dispersion-corrected density functional theory (DFT-D) method is an implementation of DFT which includes the dispersion-correction to consider van der Waals interactions. By using DFT-D, Khalkhali et al 39 studied the bulk and surface properties of gypsum.…”

“…38,39 Besides, the dispersion-corrected density functional theory (DFT-D) method is an implementation of DFT which includes the dispersion-correction to consider van der Waals interactions. By using DFT-D, Khalkhali et al 39 studied the bulk and surface properties of gypsum. After comparing their results with experimental data, they found that the DFT-D method is a promising method for studying the bulk and surface properties of gypsum, and dispersion-correction is vital for accurate modeling of van der Waals interactions between different molecules in the gypsum crystal.…”

Performance and Nanostructure Simulation of Phosphogypsum Modified by Sodium Carbonate and Alum

“…Chang et al used the COMPASS force field to study the wettability of the gypsum surface nanosphere [ 39 ]. Khalkhali et al used the COMPASS force field to study the bulk and surface properties of gypsum [ 40 ].…”