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Effects of Electric Fields Upon Energetic Molecules: Nitromethane and Dimethylnitramine

Politzer P., Murray J. S., Concha M. C., Lane P.

Central European Journal of Energetic Materials

2007

Vol. 4, nr 4

3-21

We have investigated computationally (B3PW91/6-31G**) the effects of electric fields upon certain properties - dipole moments, energies, geometries and electrostatic potentials – of two prototypical energetic molecules, nitromethane and dimethylnitramine. Fields of various strengths and in different directions were considered. The stronger fields significantly polarized the molecular charge distributions, especially when applied parallel to the C-NO2 and the N-NO2 bonds. These directions correspond to the principal polarities of the ground-state molecules, which these parallel fields either reinforce or counteract. With respect to geometries, the changes are primarily conformational, e.g. rotation of the methyl groups or inversion of the pyramidal nitrogen in (H3C)2N-NO2.

Electrostatic models for electronically inverse hosts

Rohmer M.-M., Benard M., Blaudeau J.-P.

Bulletin of the Polish Academy of Sciences. Chemistry

1998

Vol. 46, No. 3

331-347

Ab initio Hartree-Fock calculations have been carried out in order to get a better understanding of the formation and stability of inclusion and encapsulation complexes. The "electronically inverse" host anions known to encapsulate anionic species are formed in solution by means of a template mechanism that tends to maximize the electrostatic potential at the place of the guest anion. A correlation is provided between the topology of the host and its Molecular Electrostatic Potential (MEP) distribution that explains from simple geometric considerations the differences between electronically normal and electronically inverse hosts, and shows that the host cage tends to get adapted not only to the shape of the guest molecule, but also to its electrostatic potential distribution.