Formation of PS through radiative association

Abstract

Quantum chemical calculations within the multireference configuration interaction with single and double excitation level of theory are presented and used to obtain the rate coefficient for the radiative association of phosphorus and sulfur atoms to form phosphorus monosulfide (PS). The contribution of the 1 2 + state to spontaneous radiative association of the P( 4 S) and S( 3 P) atoms is more significant for forming PS. The computed rate constant can be represented over the 300-450 K temperature range by the form k(T) = 2.07 × 10 −22 (T∕300) 6.21 exp(−371∕T) cm 3 s −1 and over the 450-14,000 K temperature range by the relation k(T) = 3.68 × 10 −18 (T∕300) 0.337 exp(−3603∕T) cm 3 s −1 , where T is in K.

Phosphine Reactivity and Its Implications for Pyrolysis Experiments and Astrochemistry

“…The study of CP and SiP formation considered the range of 300−14,100 K, and in both cases, rate coefficients increase by increasing the temperature, following a modified Arrhenius expression. Also, the radiative association between P and S atoms producing phosphorus monosulfide (PS), in its doublet ground state, has been investigated by de Almeida et al, 23 and the reaction kinetics of PO formation in the interstellar medium (ISM) was studied by Garci ́a de la Concepcioń et al 24 Phosphine ice, the phosphorus analogue to ammonia (NH 3 ), is a plausible major phosphorus constituent of comets. However, recent searches in the gaseous coma of a few comets turned out unsuccessful, providing upper limits not significant enough to conclude whether PH 3 locks most of the phosphorus in these small bodies.…”

“…The study of CP and SiP formation considered the range of 300–14,100 K, and in both cases, rate coefficients increase by increasing the temperature, following a modified Arrhenius expression. Also, the radiative association between P and S atoms producing phosphorus monosulfide (PS), in its doublet ground state, has been investigated by de Almeida et al, and the reaction kinetics of PO formation in the interstellar medium (ISM) was studied by García de la Concepción et al…”