Published online by Cambridge University Press: 10 February 2011
We are performing constant-NPT Monte Carlo calculations of the physical properties of crystalline TATB. Our approach is to employ an atomistic model in which the individual molecules are treated as semi-rigid entities. Each molecule is allowed to undergo rigid translations and rotations, and in some cases limited intramolecular flexibility is conferred on the molecules via exocyclic torsions. Additionally, the size and shape of the simulation box is allowed to vary. Our immediate interest is in computing the density, lattice energy, lattice constants, and other structural parameters as a function of temperature. Preliminary results indicate that simulations involving only two molecules suffice for calculations of the energy and density, but that more molecules are required to compute the lattice constants. Intramolecular flexibility is important, particularly at higher temperatures.