Solvent Density Dependence of Translational Diffusion of Transient Radicals in the Medium-Density Region of Trifluoromethane and Carbon Dioxide
Solvent Density Dependence of Translational Diffusion of Transient Radicals in the Medium-Density Region of Trifluoromethane and Carbon Dioxide
复制标题
三氟甲烷和二氧化碳中等密度区域瞬态自由基平移扩散的溶剂密度依赖性
DOI：
10.1021/jp964085v
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发表时间：
1997
影响因子：
3.3
通讯作者：
N. Hirota
中科院分区：
文献类型：
--
作者：
Y. Kimura;D. Kanda;M. Terazima;N. Hirota
Translational diffusion constants of transient radicals produced by photochemical reactions of pyrazine, α-naphthoquinone, quinoxaline, and benzophenone with triethylamine (TEA) have been measured in trifluoromethane from ρr = 1.4 to 2.0, and α-naphthoquinone with TEA in carbon dioxide from ρr = 1.2 to 1.93, where ρr is the reduced density by the critical density of the solvent. The diffusion constants of the transient radicals almost linearly depend on the reciprocal of the solvent viscosity in the measured density region. The diffusion constants of the radicals are relatively smaller than those of stable molecules of similar molecular sizes, and the difference becomes smaller with increasing the molecular size, as is observed in liquid solution. However, the difference is smaller than that observed in the liquid solvent, which suggests that the effect of the solute-solvent attractive interaction on the diffusion constant is smaller in fluids at the medium-density region than in liquids.
