Synthesis, structural characterization and spectroscopic studies of bis tetramethylammonium hexabromostannate [N(CH3)4]2SnBr6

The Raman and infrared spectra at room temperature are recorded in the wavenumber range 10-3600 cm−1 and 400-4000 cm−1, respectively. Ab-initio calculations have been performed using the Gaussian 98 program at room temperature. Hartree-Fock (HF) and B3LYP density functional theory (DFT) methods with 6-31G (d) and LanL2DZ basis sets were used to obtain equilibrium geometry and the fundamental vibrational frequencies and spectroscopic intensities of the free polyhedra [(N(CH3)4]+ and [SnBr6]2-. The overall results are consistent with the experimental ones and group theory analysis, but also clearly show extra features that suggest disorder of the methyl groups of TMA.