Ab Initio Study of the Electric Dipole Transition Moment for the Electronic X toC Transition in Acetylene: Theoretical Predictions of the Absorption and Magnetic Circular Dichroism Intensities

摘要

The electric dipole transition moment has been cancelled a priori for theelectronic transition as a function of R(C-C), using ab initio quantum chemical techniques including state averaged, complete active space MCSCF and multireference CI. The transition moment is then averaged over the vibrational wavefunctions for the C-C stretch, and theoretical predictions are made for the absorption oscillator strength and the magnetic circular dichroism (MCD) intensities, for the lowest four vibrational bands originating from v=0 in X. This study predicts an oscillator strength for absorption of f=0.157 (summed over