Vibrational and rotational relaxation of HCl in collisions with Ar. Quasiclassical trajectories on model potential-energy surfaces

Journal Article · Thu Dec 31 23:00:00 EST 1981 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100394a010· OSTI ID:6780599

Thompson, D L

State-to-state energy-transfer cross sections are calculated for Ar + HCl collisions by using quasiclassical trajectories and model potentials. Interest is focused upon relaxation from high vibration-rotation states. Calculations are reported for initial vibrational states v/sub i/ = 0, 2, 4, and 6 and initial rotational states J/sub i/ = 10, 20, and 30. Most of the calculations are for relative translational energy 0.5 eV, but for the case v/sub i/ = 6, J/sub 2/ = 20 calculations were also carried out for E/sub rel/ = 0.3 and 0.8 eV. Studies were made for two sets of values of the parameters for the pairwise additive model potential function. The results show that the relaxation of highly excited HCl involves multiple-quantum, vibrational-rotational transfers. The detailed cross sections show that as the system cascades down the vibrational ladder there are increases in rotational energy. Increasing rotational excitation causes a large enhancement in the vibrational energy transfer. Increasing the collision energy from 0.3 to 0.8 eV leads to minor changes or no change in the energy-transfer cross sections. It is suggested that simple models based on the energy changes associated with the transitions can be used to describe the cross sections for vibrational energy transfer. Variation of the potential parameters does not lead to significant differences in the results.

• Research Organization: Los Alamos Scientific Lab., NM
• OSTI ID: 6780599
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Journal Issue: 5 Vol. 86:5; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
COLLISIONS
CROSS SECTIONS
DATA
DIAGRAMS
EEV RANGE
ELEMENTS
ENERGY
ENERGY LEVELS
ENERGY RANGE
ENERGY TRANSFER
EQUATIONS
EXCITED STATES
EXPERIMENTAL DATA
FLUIDS
GASES
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
MOLECULE COLLISIONS
NONMETALS
NUMERICAL DATA
PARAMETRIC ANALYSIS
POTENTIAL ENERGY
QUANTUM NUMBERS
RARE GASES
RELAXATION
ROTATIONAL STATES
SCATTERPLOTS
STATISTICAL DATA
SURFACES
VIBRATIONAL STATES