Ensemble equivalence for counterion condensation on a two-dimensional charged disk.

Phys Rev E Stat Nonlin Soft Matter Phys

The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai 600113, India.

Published: January 2012


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Article Abstract

We study the counterion condensation on a two-dimensional charged disk in the limit of infinite dilution, and compare the energy-temperature relation obtained from the canonical free energy and microcanonical entropy. The microcanonical entropy is piecewise linear in energy, and is shown to be concave for all energies. As a result, even though the interactions are long-ranged, the energy-temperature relation and hence the counterion condensation transition points are identical in both the ensembles.

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