Comprehensive absolute line strengths analysis of the 28SiH4 octad: The 24 sub–bands of the octad in the region of 2600–3400 cm−1

Abstract

Absolute line strengths of ${}^{28}$SiH${}_4$ were measured for the first time with a Bruker Fourier transform infrared spectrometer IFS125HR and analyzed in the 2600–3400 cm⁻¹ region where the eight different bands (twenty four sub–bands) of the SiH${}_4$ octad are located. More than 1300 absolute strengths of lines belonging to the $F_2$, $F_1$, and $E-$type sub–bands of the octad ($J^{\text{max}}=22$) were determined from the fit of Hartmann–Tran profile to their experimental line shapes and were used then as the initial information in the fit of the effective dipole moment parameters of the octad. The derived set of 19 fitted parameters reproduce 1300 initial absolute line strengths of the ${}^{28}$SiH${}_4$ octad with $d_{\text{rms}}$ deviation of 4.6%. A list of the analyzed transitions is presented as the Supplementary data to this paper.