Using the B3PW91/6-31G(d) computational procedure, we fnd two types of complexes to be formed between aliphatic amines and 2,4,6-trinitrotoluene (TNT). Type 1 are noncovalent, primarily electrostatic interactions that occur in the vicinities of the NO2 groups; Type 2 are δ-adducts, at carbons 1, 3 and 5. In Type 1, the TNT framework is very little affected. In Type 2, however, the site of the complex becomes quasi-tetrahedral, with longer bonds to its neighbors in the ring; the C-NO2 bonds are shortened. The Type 1 complexes have weakly negative (attractive) interaction enthalpies. For one of them, utilizing a chargetransfer formalism, we obtained a wave length for an electronic transition to a low-lying dative excited state that is in good agreement with observed values. The Type 2 interaction enthalpies are near-zero or even positive; however all of the complexes correspond to energy minima (no imaginary frequencies). For one of the Type 2, a transition state to a nitronic acid was found, with an activation enthalpy of only 5.6 kcal/mole. This indicates a possible route for amine-induced decomposition of TNT.
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