Negative heat capacity of sodium clusters
نویسندگان
چکیده
منابع مشابه
Negative heat capacity for a cluster of 147 sodium atoms.
There exists a surprising theoretical prediction for a small system: its microcanonical heat capacity can become negative. An increase of energy can-under certain conditions-lead to a lower temperature. Here we present experimental evidence that a cluster containing exactly 147 sodium atoms does indeed have a negative microcanonical heat capacity near its solid to liquid transition.
متن کاملRemarks on Negative Heat Capacities of Clusters
The concept of negative heat capacities of clusters has been examined and argued. This discussion examines the arguments and concepts with the goal of clarifying the inherent ambiguities in the concept itself. We also show how one must use caution with this and related concepts that extend to nonequilibrium systems properties that are well defined just for equilibrium systems. INTRODUCTION—PECU...
متن کاملComment on " Negative Heat Capacity for a Cluster of 147 Sodium Atoms "
In a recent letter [1], Schmidt et al. analyze a region where the specific heat of a Na + 147 cluster becomes negative. In Boltzmann-Gibbs (BG) statistical mechanics the specific heat can never be negative in the canonical ensemble. However, as the authors are well aware, no such property is valid in general for the microcanonical ensemble. This is indeed the case of a variety of physical situa...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2003
ISSN: 0163-1829,1095-3795
DOI: 10.1103/physrevb.67.165401