title: Virial coefficients and demixing in the Asakura-Oosawa model.
abstract: The problem of demixing in the Asakura-Oosawa colloid-polymer model is considered. The critical constants are computed using truncated virial expansions up to fifth order. While the exact analytical results for the second and third virial coefficients are known for any size ratio, analytical results for the fourth virial coefficient are provided here, and fifth virial coefficients are obtained numerically for particular size ratios using standard Monte Carlo techniques. We have computed the critical constants by successively considering the truncated virial series up to the second, third, fourth, and fifth virial coefficients. The results for the critical colloid and (reservoir) polymer packing fractions are compared with those that follow from available Monte Carlo simulations in the grand canonical ensemble. Limitations and perspectives of this approach are pointed out.
authors.affiliation: Instituto de Energías Renovables, Universidad Nacional Autónoma de México (U.N.A.M.), Temixco, Morelos 62580, Mexico.
authors.forename: Mariano
authors.initials: M
authors.lastname: López de Haro
authors.affiliation: Facultad de Ciencias Físicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Tejero
authors.affiliation: Departamento de Física and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura, E-06071 Badajoz, Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Santos
authors.affiliation: Departamento de Física and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura, E-06071 Badajoz, Spain.
authors.forename: Santos B
authors.initials: SB
authors.lastname: Yuste
authors.affiliation: Department of Mathematics and Computer Science, University of Messina, Viale F. Stagno D'Alcontres 31, I-98166 Messina, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Fiumara
authors.affiliation: CNR-IPCF, Viale F. Stagno d'Alcontres, 37-98158 Messina, Italy.
authors.forename: Franz
authors.initials: F
authors.lastname: Saija