Rotational alignment by stimulated Raman pumping: C2H2(ν″2=1, J″)

Abstract

Articles you may be interested inDirect, spectroscopic measurement of the rotational state distribution of HCl fragments from the vibrational predissociation of ν2=1 (HCl)2 produced by stimulated Raman excitation Study of collisional effects on band shapes of the ν1/2ν2 Fermi dyad in CO2 gas with stimulated Raman spectroscopy. I. Rotational and vibrational relaxation in the 2ν2 band

Collisional effects on angular momentum orientation in acetylene X̃ 1Σg+ (ν2″=1,j″). I. Preparation, detection and conservation in single collisions

“…Results of such experiments have been presented in Ref. 6. The achievable alignment is significant, for j f ϭ3, about A 0 (2) ϭϪ0.9 for S-branch excitation and A 0…”

Collisional effects on angular momentum orientation in acetylene X̃ 1Σg+ (ν2″=1,j″). II. Disorientation by rotationally elastic and multiple inelastic collisions

“…Measurements of alignment decay show about the same magnitude. 7,19,31 The collisional orientation decay rate is approximately one third of the average rotational depopulation rate constant of ͗k tot ͘ ϭ25Ϯ2 (s Torr) Ϫ1 . 28 Decays of orientation have also been measured at several pressures, varying the delay time between pumping and probing until the Lennard-Jones collision probability reaches 50%.…”

Spectroscopy and energetics of the acetylene molecule: dynamical complexity alongside structural simplicity

“…More comprehensive UV-scanned Raman-UV DR spectroscopic studies of this type have been performed by Zacharias and coworkers [161,162,167], examining the RET propensities for even-ÁJ population changes and fitting the associated rate constants to a model based on the energy-corrected sudden approximation and a power-gap scaling law. Zacharias and coworkers have extended their Raman-UV DR experiments investigations to investigate M J -changing self-collisions in C 2 H 2 gas, together with a microscopic model for the resulting effects on molecular alignment and orientation [168][169][170].…”

“…Double-resonance schemes using tunable lasers to monitor coherent Raman excitation of specific molecular rovibrational states were first reported in 1983, with two variants based, respectively, on detection by LIF in D 2 CO vapour [322] and multiphoton ionization (MPI) in NO gas [323]. Subsequent early LIF-detected Raman-UV DR experiments studied glyoxal (C 2 H 2 O 2 ) [324,325], H 2 and D 2 [326], C 2 H 2 [50,52,53,54,57,161,162,[167][168][169][170], C 2 HD and C 2 D 2 [52], and stilbene [327]. Corresponding early MPI-detected Raman-UV DR experiments examined H 2 [328][329][330], benzene and other aromatics [331][332][333][334][335], HCl [336], and N 2 [337].…”