NORMAL COORDINATE TREATMENTS OF PHOSPHORYL HALIDES

Abstract

The infrared and Raman spectra for phosphoryl chloride, thiophosphoryl chloride, phosphoryl fluoride, and thiophosphoryl fluoride were collected and examined for the probable values for the wave numbers $(\Delta\sigma)$, relative intensities I, and depolarization factors $\rho$. The $\Delta\sigma$ (I) $\rho$ values adopted are as follows: for $POCl_{3}$: 192.85 (8) 0.83, 267.39 (6) 0.64, 337.44 (7) 0.81, 486.24 (10) 0.05, 581.2 (3) 6/7, and 1289.9K (5) 0.04; for $PSCl_{3}$: 172 (5) 6/7, 247 (7) 6/7, 247 (calculated) 430 (10) 0.1, 538 (1) 6/7, and 753 K (1) P; for $POF_{3}$: 337 (W) 6/7, 467 (m) 6/7, 483 (-) P (from infrared), 875 (S) 0.05, 982 (VW) 6/7, and 1395 K (m) 0.1; for $PSF_{3}$: 940 (-) D, 874 (-) P, 695 (-) P, 440 (-) P, 402 (-) B, and 276 D. The infrared spectral data used were that of O. Cilento et. al for $PSCl_{3}$ and that of Gutowsky and Liehr for $POF_{3}$. No data were found for $POCl_{3}$ and $PSF_{3}$. Normal coordinate treatments ($C_{3\nu}$ model) were made for $POCl_{3}$, $PSCl_{3}$, $POF_{3}$, and $PSF_{3}$. These gave calculated fundamentals which agree well with the values listed above and lend support for the 247 K for $PSCl_{3}$ and 483 K for $POF_{3}$ as the missing Raman lines. The F-matrix elements were determined in such a manner that potential constants for the $PCl_{3}$ group had nearly the same values in $POCl_{3}$ and $PSCl_{3}$, those for the $PF_{3}$ group had nearly the same values in $POF_{3}$ and $PSF_{3}$,the one for the PO group had nearly the same value in $POCl_{3}$ and $POF_{3}$, and the one for the PS group had nearly the same value in $PSF_{3}$ and $PSCl_{3}$. In addition to these halides, $PFCl_{2}$ and $POFCl_{2}$ were considered. In this latter case the potential constants for $PFCl_{2}$ were correlated with those of $PF_{3}$ and $PCl_{3}$ and were used in the determination of the F-matrix elements for $POFCl_{2}$ in the same manner as given above.