- m at . m es - h al l ] 2 4 Ju n 20 05 1 Non - extensive thermodynamics of transition - metal nanoclusters 1
نویسنده
چکیده
In recent years, much study has been made by applying the non-extensive statistics (NES) to various non-extensive systems where the entropy and/or energy are not necessarily proportional to the number of their constituent subsystems. The non-extensivity may be realized in many systems such as physical, chemical and biological ones, and also in small-scale systems. After briefly reviewing the recent development in nanomagnetism and the NES, I have discussed, in this article, NES calculations of thermodynamical properties of a cluster consisting of noninteracting M dimers. With bearing in mind atomic-scale transition-metal dimers, each of the dimers is assume to be described by the two-site Hubbard model (a Hubbard dimer). The temperature-and magnetic-field dependences of the energy, entropy, specific heat and susceptibility have been calculated by changing the number of dimers, M = 1, 2, 3, · ·. It has been shown that the thermodynamical property of nanoclusters containing a small number of dimers is considerably different from that of macroscopic counterparts calculated within the conventional Boltzman-Gibbs statistics. The susceptibility and specific heat of spin dimers described by the Heisenberg model have been discussed also by employing the NES.
منابع مشابه
2 2 Ju n 20 05 1 Non - extensive thermodynamics of transition - metal nanoclusters 1
In recent years, much study has been made by applying the non-extensive statistics (NES) to various non-extensive systems where the entropy and/or energy are not necessarily proportional to the number of their constituent subsystems. The non-extensivity may be realized in many systems such as physical, chemical and biological ones, and also in small-scale systems. Bearing in mind atomic-scale t...
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In recent years, much study has been made by applying the non-extensive statistics (NES) to various non-extensive systems where the entropy and/or energy are not necessarily proportional to the number of their constituent subsystems. The non-extensivity may be realized in many systems such as physical, chemical and biological ones, and also in small-scale nanosystems. After briefly reviewing th...
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