تاثیر افزایش تعداد مولکول ها در توان گرمای مولکول C20

نوع مقاله: مقاله پژوهشی کامل

نویسندگان

1 دانشگاه گیلان

2 آزمایشگاه نانوفیزیک محاسباتی، گروه فیزیک دانشکده علوم پایه، دانشگاه گیلان

چکیده

در این پژوهش، خواص توان گرمایی مولکول فولرن C20 و اثر افزایش تعداد مولکول با استفاده از نظریه تابعی چگالی و فرموﻝبندی تابع گرین در رژیم پاسخ خطی بررسی شده است. ما سه ارایش متفاوت: Au- C20 - Au, Au- (C20)2- Au وسرانجامAu- (C20)3 – Au را در نظر می گیریم. محاسبات نشان ﻣﻲدهد که با افزایش تعداد مولکول فولرن C20 توان گرمایی افزایش ﻣﻲیابد. بعلاوه، علامت ضریب سیبک به طول وابسته است و ﻣﻲتواند برای تعداد مختلفی از مولکوﻝهای فولرن C20، مثبت (نوع p) یا منفی (نوع n) باشد. توان گرمایی، عدد شایستگی را در سیستم افزایش ﻣﻲدهد و منجر به بازدهی بیشتر وسیله ترموالکتریک خواهد شد.

کلیدواژه‌ها


عنوان مقاله [English]

Impact of increasing the number of molecules in thermopower properties of C20 molecule

نویسنده [English]

  • Hita Khalatbari 2
2 Computational Nanophysics Laboratory (CNL), Department of Physics, University of Guilan, Rasht, Iran
چکیده [English]

In this research, thermopower properties of C20 fullerene molecule and the effect of increasing the number of molecule is investigated using density functional theory and Green’s function formalism in linear response regime. We consider three different configuration: Au- C20 - Au, Au- (C20)2- Au and finally Au- (C20)3 – Au. The calculation show that increasing the number of C20 fullerene molecules in the device increases the molecular thermopower. In addition, the signs of the seebeck coefficient are length dependent and can be positive (p type) or negative (n type) for different number of C20 fullerene molecules. Thermopower, increases the figure of merit in the system and will lead to more efficient thermoelectric Device.

کلیدواژه‌ها [English]

  • Thermopower
  • C20 fullerene
  • Density functional theory
  • Green’s function
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