Density functional theory studies of structural properties, energies and natural band orbital for two new aluminate compounds

Two new aluminate compounds was prepared by the reaction of AlCl3 with KX (X = SCN−, CN−) in a 1:1 mole ratio. In these salts the aluminum atom is surrounded by three chlorine atoms and a ligand (X = SCN−, CN−). In AlCl3SCN anion, the SCN coordinates to the Al through sulfur and AlCl3CN anion the CN− coordinates to the Al center through carbon. The molecular geometry, vibrational frequencies, energies and natural bond orbital (NBO) in the ground state are calculated by using the DFT (B3LYP) methods with 6-311G* basis sets. The geometries and normal modes of vibrations obtained from B3LYP calculations are in good agreement with the experimentally observed data.

Graphical abstract.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The molecular geometry, vibrational frequencies, energies and natural bond orbital (NBO) were studied using DFT (B3LYP) methods with 6-311G* basis sets. ► HOMO–LUMO energies of compounds were calculated. ► Thermodynamic properties of compounds were performed. ► It is obvious that isomer AlCl3SCN and AlCl3CN are the stable structure at room temperature.