کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10618749 988184 2005 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Role of vibrational optical phonons in the heat capacity of K3C60
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد بیومتریال
پیش نمایش صفحه اول مقاله
Role of vibrational optical phonons in the heat capacity of K3C60
چکیده انگلیسی
The reported heat capacity C(T) data of alkali doped fulleride K3C60 is theoretically investigated in the temperature domain 5 ≤ T ≤ 25 K. Calculations of C(T) have been made within the two component scheme: one is the phonon (optic and acoustic) and the other is electronic contribution. We begin with the intercage interactions between the adjacent C60 cages and expansion of lattice due to the intercalation of alkali atoms based on the spring model to estimate vibrational optic and acoustic phonon frequencies from the dynamical matrix for the intermolecular alkali-C60 phonon mode. Lattice specific heat is well estimated from the Debye and Einstein approximation. Fermionic component as the electronic specific heat coefficient is deduced using the band structure calculations for metallic phase. Comparison of the coefficient of the normal state electron contribution to C with band structure calculations gives an estimate of the electron-phonon coupling strength. It is notice that electron correlations are essential to enhanced density of state over simple Fermi liquid approximation in the metallic phase. The present numerical analysis of specific heat shows dominating role of vibrational optical phonons.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Synthetic Metals - Volume 155, Issue 2, 15 November 2005, Pages 380-383
نویسندگان
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