title: Second virial coefficient of rod-shaped molecules and molecular dynamics simulations of the isotropic phase.
abstract: The second virial coefficient, B(2) is computed of linear rigid rods composed of m equally spaced sites interacting with sites on other rods via the hard-sphere or Weeks-Chandler-Andersen (WCA) pair potentials. The dependence of B(2) on a wide range of separation distance between the sites L and m for both types of potential is computed. Molecular dynamics simulations were carried out of the thermodynamic, static, and percolation properties of the WCA rigid rods in the isotropic phase as a function of rod number density ρ. Simple scaling relationships are discovered between thermodynamic and other static properties as a function of ρ and m, which extend well into the semidilute density range. The percolation threshold distance (PTD) between the centers of mass of the rods complies well with a mean-field random orientation approximation from low density well into the semidilute regime. The corresponding site-site PTD proved more problematic to represent by simple functions, but at high rod density, scales better with the number of sites density rather than the rod number density.
authors.affiliation: Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 OEX, United Kingdom.
authors.forename: D M
authors.initials: DM
authors.lastname: Heyes
authors.affiliation: School of Engineering & the Built Environment, Edinburgh Napier University, Merchiston Campus, 10 Colinton Road, Edinburgh EH10 5DT, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Turner
authors.affiliation: School of Engineering & the Built Environment, Edinburgh Napier University, Merchiston Campus, 10 Colinton Road, Edinburgh EH10 5DT, United Kingdom.
authors.forename: R J
authors.initials: RJ
authors.lastname: English
authors.affiliation: School of Engineering & the Built Environment, Edinburgh Napier University, Merchiston Campus, 10 Colinton Road, Edinburgh EH10 5DT, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Williams
authors.affiliation: Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznań, Poland.
authors.forename: A C
authors.initials: AC
authors.lastname: Brańka