Using the reaction of Ar(3P0, 2)+PCl3 as a source of PCl(b^1∑^+), we have measured the quenching rate constants of PCl (b, v'=0) for more than 20 quenchers. The E-V model is used to calculate the rate constants. Comparison of the calculated values with the experimental ones shows that the quenching of PCl(b) by the quencher molecules results from the electronic-to-vibrational energy resonant transfer and has relations to the Franck-Condon factors for the PCl(b, v'=0→a, v''=m) transition and the anharmonicities of the terminal bonds of the quencher molecules. In addition, the influence of the polarizability on the quenching rate constants is discussed.

Key words: PHOSPHORUS CHLORIDE, METASTABLE STATES, QUENCHING, POLARIZABILITIES