Centres de bandes et constantes d'anharmonicité de la molécule du trifluorure de phosphore PF3

In this paper, we establish interesting relationships linking rovibrational band-centers and anharmonic constants of symmetric top molecule. Using these relationships, nine accurate values of the xij and gij anharmonic constants have been deduced from the band-centers of fundamental, overtone, combination, and hot bands of the PF3 gas molecule. Taking into account the Fermi resonance between the ν3 and ν2 + ν4 bands, with a W234 = 2.86 cm–1 coupling term, the band-centers and the anharmonic constants of the molecular potential have been corrected.