title: Properties of a Method for Performing Adaptive, Multilevel QM Simulations of Complex Chemical Reactions in the Gas-Phase.
abstract: The properties of a new method of performing molecular dynamic simulations of complex chemical processes are presented. The method is formulated to give a time-dependent, multilevel representation of the total potential that is derived from spatially resolved quantum mechanical regions. An illustrative simulation is performed on a 110 atom system to demonstrate the continuity and energy conserving properties of the method. The effect of a discontinuous total potential upon the kinetic energy of the system is examined. The discontinuities in the magnitude of atomic force vectors due to changing the electronic structure during the simulation are examined as well as the effect that these discontinuities have upon the atomic kinetic energies. The method, while not conserving total energy, does yield canonical (NVT) simulations. The time reversibility property of the simulation with an extremely discontinuous total potential is discussed. The computational scaling associated with the formation of the spatially resolved, time-dependent groups is also investigated.
authors.affiliation: Department of Chemistry, Union University, 1050 Union University Drive, Jackson, Tennessee 38305 and Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755.
authors.forename: M Graham
authors.initials: MG
authors.lastname: Guthrie
authors.affiliation: Department of Chemistry, Union University, 1050 Union University Drive, Jackson, Tennessee 38305 and Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755.
authors.forename: April D
authors.initials: AD
authors.lastname: Daigle
authors.affiliation: Department of Chemistry, Union University, 1050 Union University Drive, Jackson, Tennessee 38305 and Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Salazar