Experimental rovibrational constants and equilibrium structure of phosphorus trifluoride

Abstract

Thanks to recent high-resolution Fourier transform infrared (FTIR) and pure rotational (RF/CM/MMW) measurements, several experimental values of the rotation–vibration parameters of the oblate molecule PF3 have been extracted, contributing thus to the knowledge of the molecular potential of phosphorus trifluoride. The data used are those of the fundamental, overtone and combination bands studied in the 300–1500cm−1 range. The new values are in good agreement with ones determined at low resolution, but significantly more accurate. The agreement is excellent with the available values determined by ab initio HF-SCF calculations employing the TZP/TZ2P triple-zeta basis. From the recent experimental rovibrational interaction constants αC and αB, new accurate equilibrium rotational constants Ce and Be have been derived for the symmetric top molecule PF3, which were used to derive the equilibrium geometry of this molecule: re(F–P)=1.560986 (43)Å; θe(FPF)=97.566657 (64)°.