Molecular dynamics of glass-forming liquids: Structure and dynamics of liquid metatoluidine

A molecular dynamics simulation has been performed to investigate the structure and the dynamics of liquid and supercooled metatoluidine. H-bonding and clustering has been shown to dominate the structure of the liquid. An extensive analysis of the cluster formation and of its relation with the characteristic prepeak of the static structure factor is given. It is shown that molecular association is strongly driven not only by H-bonds, but also by methyl-methyl interactions which favor specific cluster configurations. The liquid-glass transition has been followed through a calculation of the temperature variation of the molar specific heat and a mechanism has been suggested for the structural changes occurring at the phase transition. The librational dynamics of the system has been studied and recent optical Kerr effect measurements have been perfectly reproduced in a wide time regime. (C) 2002 American Institute of Physics.