High-resolution infrared spectrum of 28SiH3D from 1450 to 1710 cm−1

Abstract The ν 2 and 2 ν 6 infrared bands of 28 SiH 3 D have been recorded between 1450 and 1710 cm −1 with 0.005 cm −1 apodized spectral resolution using a Fourier transform spectrometer. Line assignments were made from J = 0 to 25 and K = 0 to 15 for the ν 2 band, from J = 0 to 20 and K = 0 to 13 for the 2 ν 6 0 band, and from J = 0 to 20 and K = 0 to 8 for the 2 ν 6 2 band. Very strong perturbations were observed in all three components of the triad system, including l -type interactions between 2 ν 6 0 and 2 ν 6 2 and Fermi interactions between ν 2 and 2 ν 6 . Observed transitions were fit using ground state constants, derived from ground state combination differences, and upper state energy levels, obtained by diagonalizing an energy matrix including Fermi resonance terms between v 2 = 1 and v 6 = 2. Molecular coefficients and their method of determination are reported.