Laser studies of the collisional quenching of electronically excited Mg(3s3p 1P1) atoms

Abstract

Quenching of the Mg(3s3p ¹P₁) state by several simple gases has been studied using pulsed laser techniques. Absolute quenching cross sections were determined by pulsed laser excitation of Mg(¹P₁) and time‐resolved measurements of 2852 Å fluorescence. Qualitative identification of major exit channels was accomplished using laser‐induced fluorescence at short time delays. Except for the inert gases and the perfluoroalkanes, the cross sections were approximately gas kinetic and correlated well with the C₆ long‐range forces coefficient to the power 0.48±0.05. In contrast to the analogous Cd(5s5p ¹P₁) level, production of Mg(³P_J) by collision‐induced intersystem crossing was negligible for all quenching molecules studied. Production of MgH was observed for H₂, CH₄, C₃H₆, C₃H₈, and n‐C₄H₁₀, but not for C₂H₂ or C₂H₄.