title: Extended Lagrangian Born-Oppenheimer molecular dynamics simulations of the shock-induced chemistry of phenylacetylene.
abstract: The initial chemical events that occur during the shock compression of liquid phenylacetylene have been investigated using self-consistent tight binding molecular dynamics simulations. The extended Lagrangian Born-Oppenheimer molecular dynamics formalism enabled us to compute microcanonical trajectories with precise conservation of the total energy. Our simulations revealed that the first density-increasing step under shock compression arises from the polymerization of phenylacetylene molecules at the acetylene moiety. The application of electronic structure-based molecular dynamics with long-term conservation of the total energy enabled us to identify electronic signatures of reactivity via monitoring changes in the HOMO-LUMO gap, and to capture directly adiabatic shock heating, transient non-equilibrium states, and changes in temperature arising from exothermic chemistry in classical molecular dynamics trajectories.
authors: Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: M J
authors: MJ
authors: Cawkwell
authors: Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Anders M N
authors: AM
authors: Niklasson
authors: Weapons Experiments Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Dana M
authors: DM
authors: Dattelbaum