کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5413169 1506618 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A three-variable theory on the translation-reorientation coupling of molecular liquids
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
A three-variable theory on the translation-reorientation coupling of molecular liquids
چکیده انگلیسی
The two-variable theory on the translation-reorientation coupling observed in the light-scattering spectra of molecular liquids is extended to include the time derivative of the orientation as one of the explicit variables. The novel “three-variable theory” has the mathematical form more proper than the two-variable one in that the shear viscosity is directly proportional to the time integration of the time-correlation function of the random shear stress and that the translation-reorientation coupling constant is given by the covariance of the random shear stress and random acceleration of the orientation. Molecular dynamics simulations on the isotropic phase of Gay-Berne fluid are performed to test the performance of the three-variable theory. The decay times of all the memory functions are much shorter than the corresponding ones of the two-variable theory, and they are rather insensitive to the density of fluid even near the isotropic-nematic transition where reorientational correlation time is long. These characteristics demonstrate that the three-variable theory provides a better starting point to discuss the translation-reorientation coupling based on the molecular interaction and liquids structure.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Liquids - Volume 147, Issues 1–2, 20 July 2009, Pages 2-8
نویسندگان
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