J. Phys. IV France 01 (1991) C7-467-C7-470
TUNABLE DIODE LASER STUDIES OF COLLISIONLESS INFRARED EXCITATION OF SF6 AND NH3 MOLECULESYu.A. KURITSYN, G.N. MAKAROV, V.R. MIRONENKO and I. PAK
Institute of Spectroscopy, USSR Academy of Sciences, Moscow Region, Troitsk SU-142092, USSR
The work was aimed at the study of collisionless excitation of molecules by intensive laser infrared (IR) radiation. Molecules of SF6 and NH3 were cooled in a pulsed supersonic jet. Excitation was provided by various lines of a TEA CO2 laser. A tunable diode laser was used for probing of molecules. The dependences have been obtained for the fraction f of molecules excited from individual rotational levels on the density Φ of the excitation energy [1-5]. A model of the laser field is proposed which gives a good description of f (Φ) in the case of one- and two-photon excitation of NH3 . It is believed that the present model will describe appropriately IR excitation of molecules of SF6 type in the region of lower discrete vibrational levels.
© EDP Sciences 1991