Fluorescence and quenching of O2(1Dgr;g) and O2(1Dgr;g)2in liquid oxygen

摘要

Liquid oxygen, oxygensol;nitrogen, and oxygensol;argon mixtures were excited by 1.060 mgr; radiation from a Nd:glass laser. The fluorescence decay was monitored at 6340 Aring;, 7030 Aring;, 1.27 mgr;, and 1.58mgr;. The quenching rate coefficient of O2(a1Dgr;g) byO2lpar;Xthinsp;3Sgr;gminus;rpar;was found to be 1.0plusmn;0.1times;10minus;18cm3sol;sec at 77deg;K. The temperature variation between 77 and 322deg;K is consistent with 2.2times;10minus;18(Tsol;300)1sol;2cm3sol;sec. Quenching by N2and argon was at least an order of magnitude slower. In every case the decay of O2(1Dgr;g)2was twice as fast as that of O2(1Dgr;g) alone, indicating that even at liquid nitrogen temperature O2(1Dgr;g)2is in rapid collisional equilibrium with O2(1Dgr;g).