Accession Number : ADA137166

Title :   Ionic Reactions of Atmospheric Importance.

Descriptive Note : Interim scientific rept. no. 1, 1 Feb 82-30 Sep 83,

Corporate Author : BIRMINGHAM UNIV (ENGLAND) DEPT OF SPACE RESEARCH

Personal Author(s) : Smith,D ; Adams,N G

PDF Url : ADA137166

Report Date : 30 Nov 1983

Pagination or Media Count : 49

Abstract : A variable-temperature flowing afterglow/Langmuir probe (FALP) apparatus has been used to study the temperature dependence of a number of electron-ion dissociative recombination coefficients, alpha e, and electron attachment coefficients, Beta, over the temperature range 200-600 K. Thus alpha e(02(+)), alpha e(NO+)) and alpha e(NH4+)) have been shown to vary inversely with temperature, T, as alpha e approximately T to the -n power with n = 0.7, 0.9 and 0.6 respectively. Alpha e(H30+)) was found to be independent of temperature. Beta(CC14), Beta(CC13F) and Beta (SF6) were all very large, close to their theoretical maximum values (approximately .0000004 cc/s at 300 K) and varied only very slowly with temperature over the available range, whereas Beta(CC12F2), Beta(CHC13) and Beta(C12) were smaller and increased appreciably with temperature. From the data, activation energies, Ea, were obtained for the dissociative attachment reactions of CC13F, CC12F2, CHC13 and C12. Thus Ea(CC13F) approximately 0.02eV, Ea(CC12F2) approximtely 0.15eV, Ea(CHC13) approximately 0.12 eV and Ea(C12) approximately 0.05 eV.

Descriptors :   *Ions, *Dissociation, *Recombination reactions, *Atmospheres, Electrons, Interactions, Coefficients, Ion ion interactions, Temperature, Attachment, Plasmas(Physics), Afterglows, Langmuir probes, Ionosphere

Subject Categories : Atmospheric Physics
      Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE