Diffusion and Friction Dynamics of Probe Molecules in Liquid n-Alkane Systems: A Molecular Dynamics Simulation Study
المؤلف
المصدر
العدد
المجلد 2019، العدد 2019 (31 ديسمبر/كانون الأول 2019)، ص ص. 1-7، 7ص.
الناشر
Hindawi Publishing Corporation
تاريخ النشر
2019-02-04
دولة النشر
مصر
عدد الصفحات
7
التخصصات الرئيسية
الملخص EN
We present a molecular dynamics simulation study of the probe diffusion and friction dynamics of Lennard-Jones particles in a series of liquid n-alkane systems from C12 up to C400 at 318 K, 418 K, 518 K, and 618 K, to investigate the power law dependence of self-diffusion of polymer liquids on their molecular weights.
Two LJ particles MY1 with a mass of 114 g/mol and MY2 with a mass of 225 g/mol are used as probes to model methyl yellow.
We observed that a clear transition in the power law dependence of n-alkane self-diffusion on the molecular weight (M) of n-alkane, Dself∼M−γ, occurs in the range C120∼C160 at temperatures of 318 K, 418 K, and 518 K, corresponding to a crossover from the “oligomer” to the “Rouse” regime.
We also observed that a clear transition in the power law dependence of the diffusion coefficient DMY2 on the molecular weight (M) of n-alkane, DMY2∼M−γ, occurs at low temperatures.
The exponent γ for DMY2 shows a sharp transition from 1.21 to 0.52 near C36 at 418 K and from 1.54 to 0.60 near C36 at 318 K.
However, no such transition is found for the probe molecule MY2 at temperatures of 518 K and 618 K and for MY1 probe at temperatures of 418 K, 518 K, and 618 K, but the power law exponent γ for MY1 at 318 K shows instead a linear or a rather slow transition.
The dependence of the probe diffusion (DMY2) on the matrix molecular weight (M) reflects a significant change of the matrix dynamics associated with the probe diffusion: a crossover from the “solvent-like” to the “oligomer” regime.
As the molecular weight of n-alkane increases, the ratio of Dself/DMY2 becomes less than 1 and the probe molecules encounter, in turn, two different microscopic frictions depending on MMY/Mmatrix and the temperature.
It is believed that a reduction in the microscopic friction on the probe molecules that diffuse at a rate faster than the solvent fluctuations leads to large deviations of slope from the linear dependence of the friction of MY2 on the chain length of the n-alkane at 318 K and 418 K.
نمط استشهاد جمعية علماء النفس الأمريكية (APA)
Lee, Song Hi. 2019. Diffusion and Friction Dynamics of Probe Molecules in Liquid n-Alkane Systems: A Molecular Dynamics Simulation Study. Journal of Chemistry،Vol. 2019, no. 2019, pp.1-7.
https://search.emarefa.net/detail/BIM-1171783
نمط استشهاد الجمعية الأمريكية للغات الحديثة (MLA)
Lee, Song Hi. Diffusion and Friction Dynamics of Probe Molecules in Liquid n-Alkane Systems: A Molecular Dynamics Simulation Study. Journal of Chemistry No. 2019 (2019), pp.1-7.
https://search.emarefa.net/detail/BIM-1171783
نمط استشهاد الجمعية الطبية الأمريكية (AMA)
Lee, Song Hi. Diffusion and Friction Dynamics of Probe Molecules in Liquid n-Alkane Systems: A Molecular Dynamics Simulation Study. Journal of Chemistry. 2019. Vol. 2019, no. 2019, pp.1-7.
https://search.emarefa.net/detail/BIM-1171783
نوع البيانات
مقالات
لغة النص
الإنجليزية
الملاحظات
Includes bibliographical references
رقم السجل
BIM-1171783
قاعدة معامل التأثير والاستشهادات المرجعية العربي "ارسيف Arcif"
أضخم قاعدة بيانات عربية للاستشهادات المرجعية للمجلات العلمية المحكمة الصادرة في العالم العربي
تقوم هذه الخدمة بالتحقق من التشابه أو الانتحال في الأبحاث والمقالات العلمية والأطروحات الجامعية والكتب والأبحاث باللغة العربية، وتحديد درجة التشابه أو أصالة الأعمال البحثية وحماية ملكيتها الفكرية. تعرف اكثر