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81.
The reaction Ar(2P2,0) + H2O → Ar + H + OH(A2Σ+)was studied in crossed molecular beams by observing the luminescence from OH(A2Σ+). No significant dependence of the spectrum on collision energy was found over the 22–52 meV region. Spectral simulation was used to obtain the OH(A) vibrational distribution and rotational temperature, assuming a Boltzmann rotational distribution. Since predissociation is known to strongly affect the rovibrational distribution, the individual rotational state lifetimes were included in the simulation program and were used to obtain the average vibrational state lifetimes. Excellent agreement with experiment was obtained for vibrational population ratios N0/N1/N2 of 1.00/ 0.40/0.013 and a rotational temperature of 4000 K. Correction for the different average vibrational lifetimes gave formation rate ratios P0/P1/P2 of 1.00/0.49/0.25. The differences between these results and those from flowing afterglow studies on the same system are discussed. Three reaction mechanisms are considered, and the vibrational prior distributions are calculated from a simple density-of-states model. Only fair agreement with experiment is obtained. The best agreement for the mechanisms giving OH(A) in two 2-body dissociation steps is obtained by assuming 1.0 eV of internal energy remains in the second step. The OH(A) vibrational population distribution of the present work is similar to that found in the photolysis of H2O at 122 nm, where there is 1.10 eV of excess internal energy. 相似文献
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P. Dek L.C. Snyder M. Heinrich C.R. Ortiz J.W. Corbett 《Physica B: Condensed Matter》1991,170(1-4):253-258
Geometry, relative stability, and vibration frequencies of hydrogen complexes — with and without the presence of vacancies and self-interstitials — are calculated. Assignments proposed by various experimental investigators for hydrogen related vibrational bands are discussed based on the relation between Si-H bond-character and stretching mode frequency. 相似文献
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Fred R. Beyette Patrick J. Stanko Eric M. Hayes Rick D. Snyder Stewart A. Feld Pericles A. Mitkas Carl Wilmsen 《Optical Review》1996,3(6):A373-A375
The architecture of an optoelectronic recirculating sorter based on the hybrid integration of CMOS logic circuitry, silicon detector/receivers and vertical cavity surface emitting lasers is presented along with the demonstration of the system. 相似文献
89.
Slaframine. Absolute stereochemistry and a revised structure 总被引:2,自引:0,他引:2
R A Gardiner K L Rhinehart J J Snyder H P Broquist 《Journal of the American Chemical Society》1968,90(20):5639-5640
90.