Molecular Dynamics simulations of uniaxial and hydrostatic compression of C 70 in the disordered phase

Abstract

Classical Molecular Dynamics simulations have been performed for solid C 70 in the disordered f.c.c. phase using a spherically averaged Lennard-Jones potential. Each molecule was treated as a spherical shell of 70 carbons with radius of 3.8 Å. Tests imposing axial elongation with fixed lateral dimensions established the elastic constants C 11 and C 12. Axial deformation with zero lateral pressure was used to predict the Young modulus and the Poisson ratio. The bulk modulus was obtained by independent triaxial tension. These elastic results determined by regression analysis and digital filtering are compared to those of C 60 at 400 K and are in good agreement with those of Krzysztof et al. [K. Krzysztof, L.A. Girifalco, J.E. Fischer, J. Phys. Chem. 99 (1995) 16804] using the Girifalco potential.