Rotational excitation of symmetric top molecules by collisions with atoms: Close coupling, coupled states, and effective potential calculations for NH/sub 3/--He

Journal Article · Thu Apr 15 04:00:00 EST 1976 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.432640· OSTI ID:7354638

Green, S

The formalism for describing rotational excitation in collisions between symmetric top rigid rotors and spherical atoms is presented both within the accurate quantum close coupling framework and also the coupled states approximation of McGuire and Kouri and the effective potential approximation of Rabitz. Calculations are reported for thermal energy NH/sub 3/--He collisions, treating NH/sub 3/ as a rigid rotor and employing a uniform electron gas (Gordon--Kim) approximation for the intermolecular potential. Coupled states are found to be in nearly quantitative agreement with close coupling results while the effective potential method is found to be at least qualitatively correct. Modifications necessary to treat the inversion motion in NH/sub 3/ are discussed briefly. (AIP)

• Research Organization: Department of Chemistry, Columbia University, New York, New York 10027
• OSTI ID: 7354638
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 64:8; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
AMMONIA
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
COLLISIONS
CRYOGENIC FLUIDS
ELEMENTS
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
FLUIDS
HELIUM
HYDRIDES
HYDROGEN COMPOUNDS
INTERMOLECULAR FORCES
MOLECULE COLLISIONS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
RARE GASES
ROTATIONAL STATES