We exactly calculate the fourth virial coefficient for hard spheres in even dimensions for D = 4, 6, 8, 10, and 12.

the virial coefficients can be obtained from statistical mechanics in connection with the intermolecular potentials. the intermolecular potential of polyatomic molecules is usually assumed to consist of a spherically symmetric component plus a contribution due to asphericaity of the molecular charge distribution. in this study, the second virial coefficients have been calculated for n2, co and ...

Most reservoir fluids contain heavy paraffinic compounds that may precipitate as a solid or solid like material called wax if the fluid is cooled down. Wax precipitation is a phenomenon of considerable importance in oil industry. An increase in aggregation results in enhanced oil viscosity. This however causes significant negative effects on production, transportation and processing of crude oi...

The virial expansion of the collective mobility ~sedimentation! coefficient is considered for hard sphere suspensions at equilibrium. The term of the second order in volume fraction, which involves three-particle hydrodynamic interactions, is calculated with high accuracy. To achieve that we represent the collective mobility coefficient as the sum of convergent integrals over particle configura...

intermolecular potential energy surface (ips) for protein — protein has been examined using rhf, dft-b3lypand mp2 levels of theory with 6-31g, 6-31g* basis sets. a number of basis sets were used in order to evaluatethe basis set effects, at all three levels of theory, basis sets has significant effects on the calculated potentialenergy curves (including position, depth and width of the potentia...

Knowledge of the pair and three-body potential-energy surfaces of helium is now sufficient to allow calculation of the third density virial coefficient, C(T), with significantly smaller uncertainty than that of existing experimental data. In this work, we employ the best available pair and three-body potentials for helium and calculate C(T) with path-integral Monte Carlo (PIMC) calculations sup...

In this paper we give a method for constructing systematically all simple 2-connected graphs with n vertices from the set of simple 2-connected graphs with n-1 vertices, by means of two operations: subdivision of an edge and addition of a vertex. The motivation of our study comes from the theory of non-ideal gases and, more specifically, from the virial equation of state. It is a known result o...

It is surprisingly di cult to calculate analytic expressions for virial coe cients. Even the exact calculation of the second virial coe cient is in general extremely di cult. If particles have no other interaction than hard core repulsion, things are slightly easier. In the isotropic phase, the second virial coe cient B 2 of two arbitrary, convex particles A and B can be determined by [1]