Dataset on the crystal structure and electronic properties of kaolinite edge surfaces.

The data presented in this paper characterize stable kaolinite edge surfaces. Their equilibrium structure is obtained by DFT methods using the first-principles package CASTEP. The calculations are performed using a basis set of plane waves in the PBE exchange-correlation potential. The dispersion forces are taken into account using the semi-empirical Grimme-D2 correction. For selected kaolinite surfaces: (001),(001¯),(010),(110) the paper presents their optimized crystal structure, values of terminal hydroxyl groups charges, density of electronic states, and work function. The presented data allow characterizing the stability of the surfaces and giving their comparative evaluation. This set of surfaces can be used for a comparative study of adsorption of atoms, ions and other molecular systems.

Mechanism of Cs Immobilization within a Sodalite Framework: The Role of Alkaline Cations and the Si/Al Ratio.

Conditioning of radioactive waste generated from the operation of medical institutions, nuclear cycle facilities, and nuclear facilities is important for the safety of the environment. One of the most hazardous radionuclides is radioactive cesium. There is a need for more effective solutions to contain radionuclides, especially cesium (Cs+). Geopolymers are promising inorganic materials that can provide a large active surface area with adjustable porosity and binding capacity. The existence of nanosized zeolite-like structures in aluminosilicate gels was shown earlier. These structures are candidates for immobilizing radioactive cesium (Cs+). However, the mechanisms of their interactions with the aluminosilicate framework related to radionuclide immobilization have not been well studied. In this work, the influence of alkaline cations (Na+ or K+) and the aluminosilicate framework structure on the binding capacity and mechanism of interaction of geopolymers with Cs+ is explored in the example of a sodalite framework. The local structure of the water molecules and alkaline ions in the equilibrium state and its behavior when the Si/Al ratio was changed were studied by DFT.

Structural and electronic characteristic dataset of the water on basal surface the cis- and trans-vacant variety of a montmorillonite.

The data given in the paper were obtained using CASTEP based on the density functional theory (DFT) applying a basis set of plane waves and PBE exchange-correlation functional. Van der Waals interactions were considered by the Grimme-D2 semi-empirical correction. The data include the optimized geometry and electronic properties of the equilibrium state of the non-hydrated cis- and trans-vacant variety of a Na-montmorillonite (MMT) and its state after the adsorption of water molecules. The data on hydration shells formed by the Na+ cation on the basal surface of MMT are also presented. The data are presented on the behavior of crystalline hydroxyl groups and water molecules during their adsorption. Data files of the optimized crystal structures and electronic properties can be read by the public text editors.