Accession Number : ADA133942

Title :   Collisional Energy Exchange in Polyatomic Molecules.

Descriptive Note : Final technical rept. 1 Jan 80-31 Dec 82,


Personal Author(s) : Ryali,S B ; Fenn,J B

PDF Url : ADA133942

Report Date : 21 Aug 1983

Pagination or Media Count : 15

Abstract : Fourier Transform Infrared Spectrometry (FTIS) has been used to study several kinds of gas-gas and gas-surface collision processes brought about with and in supersonic free jets in vacuo. Following are some key results: (1) Terminal distributions of rotational energy in free jets of CO and CO2 show a non-Boltzmann distribution that can be characterized by a two-temperature model and explained in terms of competition between rotation-rotation and rotation-translation transfers. (2) Spectra of CO2 molecules excited by collisions with N2 molecules indicated similar two-temperature distributions, possibly due to secondary collisions between excited CO2 and N2. (3) The accommodations of vibrational and rotational energy during collisions between CO, CO2 and NO molecules and hot platinum surfaces has been determined over a range of surface temperatures. (4) Excess internal energies have been determined in nascent CO and CO2 molecules formed respectively by catalytic oxidation of C and CO on a platinum surface. An energy balance indicates that about 1/3 of the available reaction energy is absorbed by the surface, the remainder going mostly into vibrational modes of product molecules.

Descriptors :   *Molecule molecule interactions, *Energy transfer, *Jet flow, *Fourier spectroscopy, *Infrared spectroscopy, Polyatomic molecules, Fourier transformation, Molecular rotation, Energy, Distribution, Gas surface interactions, Collisions, Catalysis, Carbon monoxide, Carbon dioxide, Nitrogen, Molecular vibration, Surface temperature, Nitrogen oxides, Vacuum, Molecular beams, Excitation, Cross sections

Subject Categories : Fluid Mechanics
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE