Excitation spectrum of a 300:1 mixture at a total pressure of , following the photodissociation at . The transitions associated with ground-state levels are indicated. The delays between pump and probe laser pulses are 1, 4, and for the upper, middle, and bottom spectra, respectively. The arrows indicate the laser wavelengths used to probe the time dependence of the population (filled arrows: on-resonance, open arrows: off-resonance).
On-resonance (top), off-resonance (middle), and difference LIF signal (bottom) at pressure and approximately of . In the upper panel the 14-3 feature is probed at . The off-resonance signal is recorded with the probe laser wavelength tuned to . The resulting signal is an average of 84 laser shots. The solid line represents a single-exponential fit to the data as described in the text, the dashed line is an extrapolation of the fit to zero delay time, and the dotted line is the signal baseline.
decay constants as a function of pressure. The top panel shows data for and the bottom panel for . The error bars represent the confidence limits of the nonlinear fits to the LIF data within two standard deviations. The solid lines show weighed linear fits to the decay constant data.
LIF signal as a function of time delay for three different total pressures. The solid lines correspond to nonlinear fits to the data, as described in the text, the dashed lines are extrapolations of the fits to zero delay time, and the dotted lines represent the signal baseline. The signal points shown are averages of 42 (top, middle) and 49 laser shots (bottom).
Comparison of calculated and experimental rate coefficients for the vibrational energy relaxation of by near room temperature. Experiment: this work (closed triangles), Park and Slanger (Ref. 13) (closed circle), Smith and co-workers (Refs. 12, 20, and 21) (open circles), Ahn et al. (Ref. 27) [open square; the thick dashed line shows the rescaled by a factor of 8 result of Adamovich et al. (Ref. 27)]. Theory: Billing and Kolesnick (Ref. 30) (double-dot-dashed line with crosses showing the calculated points), Hernández et al. (Ref. 29) (dotted line), Adamovich et al. (Ref. 27) (dashed line), Coletti and Billing (Ref. 26) (dot-dashed line), and Kirillov (Ref. 28) (solid line).
Article metrics loading...
Full text loading...