The hot bands of silane between 2120 and 2270 cm−1

The infrared spectrum of the SiH4 molecule has been recorded between 2040 and 2320 cm−1 using the high-resolution Fourier interferometer of the Laboratoire de Photophysique Moléculaire (Orsay, France). The resolution was 5.4 × 10−3 cm−1. In this region, many lines were previously analyzed and assigned to the ν1/ν3 stretching dyad of 28SiH4, 29SiH4, and 30SiH4 molecules [J. Mol. Spectrosc. 143 (1990) 35]. However, several lines in the spectrum were not assigned. The results obtained in our previous study [J. Mol. Spectrosc. 197 (1999) 307] of the infrared spectrum of 28SiH4, in the bending-stretching tetrad region at 3100 cm−1, enabled us to assign 204 of the observed transitions to hot bands (the ν1 + ν2/ν1 + ν4/ν2 + ν3/ν3 + ν4 bending-stretching tetrad minus the ν2/ν4 bending dyad). These transitions were used to refine the set of the Hamiltonian parameters of the bending-stretching tetrad. The analysis is performed using the tensorial formalism developed in Dijon for tetrahedral molecules and implemented in the STDS software (http://www.u-bourgogne.fr/LPUB/shTDS.html).