Hybrid density functional theory and quadratic complete basis set ab initio computational study of structural properties, vibrational spectra, and bond dissociation energy for methyl aluminum and methyl gallium

Abstract

Geometries, harmonic frequencies, and homolytic and heterolytic bond dissociation energies were computed with ab initio and density functional theory (DFT) methods, the target being to determine the stability of GaCH 3 and AlCH 3, generate their infra-red spectra, and evaluate the accuracy of hybrid DFT methods for these and similar molecular systems against highly accurate ab initio methods. For this study, the ab initio methods HF, MP2, CCSD(T), and quadratic complete basis set (CBSQ) were selected. Their computational data were used for comparison with DFT (B3LYP, B3P86, and B3PW91) computed values. The stability and physical properties of the GaCH 3 and AlCH 3 organometallic complexes are discussed on the basis of these computational results.