Coumarins in the gaseous phase. I. Stimulated emission of coumarin vapors in the range 485–520 nm

Lasing in the 485-520 nm range was observed for the first time in vapors of coumarin 153 (C153), 7-diethylamino-3(2'-benzoxazolyl)-coumarin, C7, and C6 mixed with buffer gases. The pressure was about 35 atm and the vapors were excited with the third harmonic of a neodymium laser (355 nm).