Debye-Hückel-Bjerrum theory for charged colloids

Instituto de Fı́sica, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970 Porto Alegre (RS), Brazil
Physica A: Statistical Mechanics and its Applications (Impact Factor: 1.73). 09/1998; 258(3-4):341-351. DOI: 10.1016/S0378-4371(98)00238-6
Source: arXiv


We formulate an extension of the Debye-Hueckel-Bjerrum theory [M. E.
Fisher and Y. Levin, Phys. Rev. Lett. 71, 3826 (1993)] to the fluid
state of a highly asymmetric charged colloid. Allowing for the formation
of clusters consisting of one polyion and n condensed counterions, the
total Helmholtz free energy of the colloidal suspension is constructed.
The thermodynamic properties, such as the cluster-density distribution
and the pressure, are obtained by the minimization of the free energy
under the constraints of fixed number of polyions and counterions. In
agreement with the current experimental and Monte Carlo results, no
evidence of any phase transition is encountered.

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