A review of the literature about calculating the adsorption properties of arsenic onto mineral models using density functional theory (DFT) is presented. Furthermore, this work presents DFT results that show the effect of model charge, hydration, oxidation state, and DFT method on the structures and adsorption energies for As (oxyhydr)oxide cluster models were calculated using planewave and cluster-model DFT methods.

Six possible complexes of glyphosate (O-PO(OH)-CH2NH2+CH2CO2H) with an Fe-hydroxide dimer were modeled with hybrid molecular orbital/density functional theory calculations to establish the nature of the bonds of glyphosate on goethite (alpha-FeOOH). Monodentate and bidentate coordination of the phosphonate moiety were considered, using three forms of the glyphosate molecule appropriate for different pH ranges: glyphosate with both phosphonate and amino moieties protonated, glyphosate with unprotonated phosphonates, and glyphosate with both unprotonated phosphonates and no hydrogen ion on the amino group. The calculated infrared vibrational modes were compared to experimental values, finding particularly good agreements with the monodentate complexes in all the pH ranges.

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Energy- and angle-resolved intensities are reported for the scattering of argon atoms off the surface of liquid indium just above the melting temperature, for two different argon incident energies. The higher incident energy results show significant energy transfer from argon to liquid atoms, and the angular distribution of scattered argon atoms is relatively sharply peaked near the specular angle. The lower incident energy results show a small amount of energy transfer from liquid atoms to argon atoms, the energy distribution of the scattered argon atoms is nearly thermal, and the angular distribution is much less sharply peaked, although still not completely thermal. Molecular dynamics simulations of these experiments are performed, and most of the results are in reasonable agreement with experiment. Analysis of the simulation trajectories helps to provide a microscopic understanding of the experimental results.

The interactions of HNO(3) and NO(3)(-) with kaolinite surfaces are important in the reaction of airborne clay mineral particles with atmospheric trace gases. Theoretical calculations at the B3LYP/6-311++G(d,p) level were performed on surface clusters of HNO(3) on kaolinite, on monodentate, on bidentate, and on two bridged complex structures of NO(3)(-) on kaolinite and on gas phase and solvated NO(3)(-). The results are compatible with the ranges assigned in the literature for NO(3)(-) on mineral surfaces for the frequency of the vibrational symmetric stretches (ν(1)) and for the low-frequency branch of the asymmetric stretches (ν(3)), with slightly higher frequencies reported for the bridged models. For the higher-frequency branch of the asymmetric stretches measured on kaolinite (Angelini et al.), our calculations match the assigned values for the monodentate surface complex, while predicting an inverse assignment for the frequencies of the bidentate and bridged complexes.