Vibrational energy transfer in selectively excited diatomic molecules. [Relaxation rates, self-relaxation, upper limits]
Single rovibrational states of HCl(v=2), HBr(v=2), DCl(v=2), and CO(v=2) were excited with a pulsed optical parametric oscillator (OPO). Total vibrational relaxation rates near - resonance quenchers were measured at 295/sup 0/K using time resolved infrared fluorescence. These rates are attributed primarily to V - V energy transfer, and they generally conform to a simple energy gap law. A small deviation was found for the CO(v) + DCl(v') relaxation rates. Upper limits for the self relaxation by V - R,T of HCl(v=2) and HBr(v=2) and for the two quantum exchange between HCl and HBr were determined. The HF dimer was detected at 295/sup 0/K and 30 torr HF pressure with an optoacoustic spectrometer using the OPO. Pulsed and chopped, resonant and non-resonant spectrophones are analyzed in detail. From experiments and first order perturbation theory, these V - V exchange rates appear to behave as a first order perturbation in the vibrational coordinates. The rotational dynamics are known to be complicated however, and the coupled rotational - vibrational dynamics were investigated theoreticaly in infinite order by the Dillon and Stephenson and the first Magnus approximations. Large ..delta..J transitions appear to be important, but these calculations differ by orders of magnitude on specific rovibrational transition rates. Integration of the time dependent semiclassical equations by a modified Gordon method and a rotationally distorted wave approximation are discussed as methods which would treat the rotational motion more accurately. 225 references.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 6229112
- Report Number(s):
- LBL-8208; TRN: 79-012645
- Resource Relation:
- Other Information: Thesis
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
DEUTERIUM COMPOUNDS
ROTATIONAL STATES
VIBRATIONAL STATES
HYDROBROMIC ACID
HYDROCHLORIC ACID
COORDINATES
ENERGY TRANSFER
EXCITED STATES
FLUORESCENCE
INTEGRALS
LIMITING VALUES
MOLECULES
OSCILLATORS
PERTURBATION THEORY
PHOTONS
RELAXATION
RESONANCE
SEMICLASSICAL APPROXIMATION
TIME DEPENDENCE
ELECTRONIC EQUIPMENT
ELEMENTARY PARTICLES
ENERGY LEVELS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
LUMINESCENCE
MASSLESS PARTICLES
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory