High resolution infrared spectra of the first and second stretching overtone band systems of 123SbD3

Abstract: The high resolution infrared spectrum of the mono-isotopic species 123SbD3 has been studied in the regions of the first and second Sb–D stretching overtones, from 2600 to 2800cm−1 and from 3900 to 4100cm−1, respectively. In both regions only two almost degenerate bands of similar intensity have been observed, one parallel and the other perpendicular, corresponding to the low-lying states in the manifolds of the excited vibrational states. These bands have been identified as 2ν 1(A 1)/ν 1 + ν 3(E) in the first overtone and 3ν 1(A 1)/2ν 1 + ν 3(E) in the second overtone band system. About 1700 transitions with have been assigned to the 2ν 1(A 1)/ν 1 + ν 3(E) and about 700 with to the 3ν 1(A 1)/2ν1+ ν 3(E) dyad. The transitions assigned to each dyad have been fitted simultaneously since the A 1/E excited states are affected by strong Coriolis and k-type perturbations treated explicitly in the model. Eventually, the extent to which the parameters resulting from the analyses fulfill the local mode theory requirements has been evaluated. Differently from SbH3, the deuterated species does not reach true local mode behavior, even in the second overtone. [Copyright &y& Elsevier]