The molecular structure of kaolinite–potassium acetate intercalation complexes: A combined experimental and molecular dynamic simulation study

摘要

The kaolinite (Kaol) intercalated with potassium acetate (Ac) was prepared and characterized by X-ray diffractionud(XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetry. Molecular dynamic simulation wasudperformed to investigate the structure of Kaol–Ac intercalation complex and the hydrogen bonds between Kaol and intercalated Ac andwater using INTERFACE forcefield. The acetate anions andwater arranged in a bilayer structureudin the interlayer space of Kaol. The potassium cations distributed in the interlayer space and strongly coordinatedudwith acetate anions aswell aswater rather than keyed into the ditrigonal holes of tetrahedral surface of Kaol. Strongudhydrogen bonds formed between the hydrogen atoms of hydroxyl on the octahedral surface and oxygen atoms ofudboth acetate anions and water. The acetate anions andwater also weakly bonded hydrogen to the silica tetrahedraludsurface through their hydrogen atoms with the oxygen atoms of silica tetrahedral surface.