Absolute local mode vibrational band intensities of AsH3

The local mode vibrational absolute band intensities of AsH3 molecule were studied experimentally and theoretically. The stretching vibrational band intensities of AsH3 were derived from the infrared spectra recorded by a Bruker IFS 120 HR Fourier transform spectrometer. A three-dimensional As–H stretching dipole moment surface (DMS) was calculated by the density functional theory method. The DMS was used to calculate the absolute band intensities, which agreed well with the observed values. The inter-bond coupling terms in the DMS expansion are found to be essential in reproducing overtone and combination band intensities in the high-energy regions.