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Nanotube Tunneling as a Consequence of Probable Discrete Trajectories

Robinson D., NASA Glenn Research Center, US

It has been recently reported that the electrical charge in a semiconductive carbon nanotube is not evenly distributed, but is divided into charge "islands [1,2]." A clear understanding of tunneling phenomena can be useful to [...]

Chemical Decomposition of Solid Cyclotrimethylene Trinitramine

Kuklja M.M., Michigan Technological University, US

Quantum-chemical simulations of the thermal decomposition of solid RDX at the Hartree-Fock level are performed. It is shown that a rupture of the N-NO2 chemical bond requires less energy for an isolated molecule than for [...]

Report on the Modeling of the Large MIS Cans

Moody E.W., Lyman J., Veirs D.K., Los Alamos National Laboratory, US

Changes in gas composition and gas pressure for closed systems containing plutonium dioxide and water are studied using a model that incorporates both radiolysis and chemical reactions. The model is used to investigate the behavior [...]

Electronic Structure Modifications Induced by Nanosize Lattice Imperfections in Molecular Crystals

Kuklja M.M., Michigan Technological University, US

A first-principles theoretical modeling of basic defects such as a molecular vacancy, a vacancy dimer, an edge dislocation, and a nano-crack in organic molecular crystals, particularly solid RDX (C3H6N6O6) and PETN (C5H8N4O12), is presented. It [...]

Large-scale Simulations of Adhesion in Dense Polymer Melts

Sides S.W., Grest G.S., Stevens M.J., Sandia National Laboratories, US

We study adhesion between a polymer melt and substrate due to tethered chains on the substrate surface. We have performed extensive molecular dynamics simulations to study the effect of tethered chain density (S), tethered chain [...]

Modeling and Mass-Distance Scaling of a Nanometer Starburst Polymer

Rothschild W.G., Wayne State University, US

We report numerical scaling of cumulative mass with intramolecular distance of a model of one of the four segments of the hyperbranched poly(propylene!imine)-dendr-DAB(CN)64 molecule. Assuming prevalent repulsive link!link forces gives a power law relation with [...]

Illustrative Modeling Studies on Elastomers and Rubberlike Elasticity

Mark J.E., The University of Cincinnati, US

Examples are given to illustrate the use of computer modeling to elucidate the structures of elastomeric polymer networks, and to provide guidance on controlling these structures to maximize mechanical properties. The first example involves simulations [...]

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