Assessment of the validity of intermolecular potential models used in molecular dynamics simulations by extended x-ray absorption fine structure spectroscopy: A case study of Sr2+ in methanol solution

Abstract

The structure of PX3 (X = Cl, Br, I) molecular liquids from X-ray diffraction, molecular dynamics simulations, and reverse Monte Carlo modeling Structure and predicted near edge x-ray absorption fine structure spectra for the surface of liquid formamide from molecular-dynamics simulation An extended xray absorption fine structure study by employing molecular dynamics simulations: Bromide ion in methanolic solution Molecular dynamics simulations have been carried out for Sr 2ϩ in methanol using different Sr 2ϩ Lennard-Jones parameters and methanol models. X-ray absorption fine structure ͑EXAFS͒ spectroscopy has been employed to assess the reliability of the ion-ion and ion-methanol potential functions used in the simulations. Radial distribution functions of Sr 2ϩ in methanol have been calculated for each simulation and compared with the EXAFS experimental data. This procedure has allowed the determinations of reliable Sr 2ϩ -methanol models which have been used in longer simulations providing an accurate description of the dynamic and structural properties of this system.

Diffusion coefficient of ionic solvation shell molecules

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Generally, their motion is found to be substantially slowed down with respect to bulk solvent molecules but still somewhat faster than that of the ion. This conclusion is usually founded on the computation of the diffusion coefficient for the subset of first solvation shell molecules: its value is larger than that of the ion and lower than that of the bulk.…”

Determination of two- and three-body correlation functions in ionic solutions by means of MD and EXAFS investigations

“…A method which uses MD radial distribution functions as relevant models in the calculation of the EXAFS structural signal of disordered systems has been employed to study the solvation shells of several ions in solution (D'Angelo et al, 1994, 1996a, 1996b, 1996c, Roccatano et al, 1998.…”

“…Alkaline and alkaline earth ions give rise to a non-regular coordination in aqueous and non-aqueous solutions (D'Angelo et al,1996b, 1996c, Roccatano et al, 1998. Nevertheless, in some cases the presence of three-body correlation functions can still be detected.…”

“…The local structure of ions dissolved in aqueous and non-aqueous solutions has been extensively studied by means of x-ray absorption spectroscopy (D'Angelo et al, 1996a, 1996b, 1996c, 1997, Roccatano et al, 1998. This technique offers the unique opportunity to probe the local coordination of ions in solution.…”

The solvation of bromide anion in acetonitrile: a structural study based on the combination of theoretical calculations and X-ray absorption spectroscopy

“…The interplay of XAS spectroscopy with quantum mechanics and numerical simulations has shown to be as an appropriate strategy to get insight into structural information on ionic aqueous solutions, [18][19][20][21][22][23][24][25][26][27] and will be explored for the case of a non-aqueous solution.…”