The path integral Monte Carlo calculated radial distributions of para-hydrogen clusters (p-H2)N consisting of N = 4−40 molecules interacting via a Lennard-Jones potential at T = 1.5 K show evidence for additional peaks compared to radial distributions calculated by diffusion Monte Carlo (T = 0 K) and path integral Monte Carlo at T ≤ 0.5 K. The difference in structures is attributed to quantum d...

By simulation and theory, we study the probability of observing N molecular centers within molecular sized volumes for a Lennard-Jones fluid near liquid-vapor coexistence. For large volumes and small N, the probability distribution differs markedly from Gaussian. The free energy per unit surface area to form empty volumes (i.e., cavities) is a rapidly varying function of the radius for small ca...

The relative performances of different implementations of the Wang-Landau method are assessed on two classes of systems with continuous degrees of freedom, namely, two polypeptides and two atomic Lennard-Jones clusters. Parallel tempering Monte Carlo simulations serve as a reference, and we pay particular attention to the variations of the multiplicative factor f during the course of the simula...

Some thermodynamic quantities for the Lennard-Jones (12,6) potential are expressed as analytical formula at an isobaric process. The parameters of Lennard-Jones gases for 18 substances are obtained by the second virial coefficient data. Also some thermodynamic quantities for benzene are calculated numerically and drawn graphically. The inflexion point of the length L which depends on temperatur...

We present a new method for the prediction of the equilibrium properties of dense gases containing hydrogen isotopes. The proposed approach combines the Feynman-Hibbs effective potential method and a deconvolution scheme introduced by Weeks et al. The resulting equations of state and the chemical potentials as functions of pressure for each of the hydrogen isotope gases depend on a single set o...

Abstract We propose the general method of proving bifurcation new solutions from relative equilibria in N -body problems. The is based on a symmetric version Lyapunov center theorem. It applied to study Lennard–Jones 2-body problem, where we have proved existence periodic or quasi-periodic solutions.

(1) MICHAEL LENNARD 1923-1986 In his Obituary to Michael Lennard printed in our August number Donald Ratcliffe referred to his love of art and literature. He was a brilliant parodist and we reprint below with kind permission two excerpts from a contribution he made as a student to the 'Black Bag'. The theme was 'hernia' and readers will recognise echoes of Browning's 'Home thoughts from abroad'...

We present a new global optimization algorithm in which the influence of the leaders in social groups is used as an inspiration for the evolutionary technique which is designed into a group architecture. To demonstrate the efficiency of the method, a standard suite of single and multi dimensional optimization functions along with the energies and the geometric structures of Lennard-Jones cluste...

A review of the properties that bond the particles under Lennard Jones Potential allow to states properties and conditions for building evolutive algorithms using the CB lattice with other different lattices. The new lattice is called CB lattice and it is based on small cubes, such the number of its vertices in a region is always greater than the number of the particles of a cluster or a region...

In this work, molecular dynamics simulation is performed to study the density and surface tension of water for a range of temperatures from 300 to 600 K. The extended simple point charge interaction potential for water is used. The particle-particle particle-mesh method, which automatically includes untruncated long-range terms, is used for the Lennard-Jones and the Coulombic terms. The results...