Laboratory simulation of tunneling reactions in interstellar ices

被引：17

作者：

Hiraoka, K ^{[1
]}

Sato, T ^{[1
]}

机构：

[1] Yamanashi Univ, Fac Engn, Kofu, Yamanashi 4008511, Japan

来源：

RADIATION PHYSICS AND CHEMISTRY | 2001年 / 60卷 / 4-5期

关键词：

tunneling reaction; chemical evolution; dark cloud;

D O I：

10.1016/S0969-806X(00)00414-X

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The reactions of the solid thin films of C2H2, C2H4 and CO deposited on the silicon substrate at 10K with cold H atoms (similar to 27K) sprayed over the solid films were studied by thermal desorption mass spectrometry and Fourier transform (FT)-IR spectroscopy. In the reaction of H with C2H2, C2H6 was found to be the major product but C2H4 could not be detected. This finding is in accord with the observation of comets Hyakutake and Hale-Bopp, i.e., C2H2 and C2H6 but no C2H4 were detected in the comae of these comets. In the reaction of H with CO, HCHO was found to be the major product but no CH3OH was detected. In all the I reactions investigated, the product yields increased drastically with decrease of temperature from similar to 50 to 10K. This may be mainly due to the increase of the sticking probability of H atoms on the solid films. The increase of the rate constant for the tunneling reaction H + C2H2 with decrease of temperature has been suggested. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：389 / 393

页数：5

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