Elastic constants and related mechanical properties of the monoclinic polymorph of the carbamazepine molecular crystal.

Brillouin scattering has been used to probe the acoustic phonons of the monoclinic (P21/c) polymorph of the drug carbamazepine (CBZ III). By sampling a variety of acoustic phonons, the complete elastic constant tensor has been determined for this CBZ polymorph. The diagonal elastic constants c11, c22, c33, c44, c55 and c66 are 10.

Computer simulations and analysis of structural and energetic features of some crystalline energetic materials.

A database of 43 literature X-ray crystal structure determinations for compounds with known, or possible, energetic properties has been collected along with some sublimation enthalpies. A statistical study of these crystal structures, when compared to a sample of general organic crystals, reveals a population of anomalously short intermolecular oxygen-oxygen separations with an average crystal packing coefficient of 0.77 that differs significantly from 0.

The elastic constants and related properties of the energetic material cyclotrimethylene trinitramine (RDX) determined by Brillouin scattering.

The acoustic phonons of cyclotrimethylene trinitramine (RDX) have been studied using Brillouin scattering. The analysis of the acoustic-phonon velocities allowed determination of the complete stiffness tensor for this energetic material. The results are compared to other recent experimental and theoretical determinations of the RDX elastic constants, bulk moduli, and shear moduli.

The elastic constants and related properties of beta-HMX determined by Brillouin scattering.

By scattering from a variety of acoustic phonons, a complete stiffness tensor has been determined for crystalline beta-HMX. The results are compared with recent experimental and theoretical determinations of the elastic constants and bulk modulus. Reasons for disagreement are discussed in terms of experimental limitations and anharmonic effects.