Photostimulated desorption and ortho-para conversion of H2 on Ag surfaces -: art. no. 096103

被引:43
作者
Fukutani, K [1 ]
Yoshida, K [1 ]
Wilde, M [1 ]
Diño, WA [1 ]
Matsumoto, M [1 ]
Okano, T [1 ]
机构
[1] Univ Tokyo, Inst Ind Sci, Meguro Ku, Tokyo 1538505, Japan
关键词
D O I
10.1103/PhysRevLett.90.096103
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
Photostimulated desorption and change of the ortho-para ratio of H-2 physisorbed on Ag at 7 K are reported. After pump laser excitation at 193 nm neutral H-2 desorbing in a nonthermal process is state selectively detected by resonance-enhanced multiphoton ionization. At weak pump laser fluence the natural ortho-para conversion of H-2 on Ag was monitored to proceed with a conversion time of similar to780 s, which is in good agreement with predictions based on an electron-exchange-hyperfine-contact model. With increasing pump laser fluence, the ortho-para ratio decreases faster, suggesting photoassisted ortho-para H-2 conversion.
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页数:4
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