Inter- and Intramolecular Bonding in 1,3,5-Triamino-2,4,6-trinitrobenzene: An Experimental and Theoretical Quantum Theory of Atoms in Molecules (QTAIM) Analysis

Chemical bonding in the triclinic phase of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) has been analyzed based on the experimental electron density derived from X-ray diffraction data obtained at 20 K. The results have been compared with those from solid state theoretical calculations. The total electron density has been analyzed in terms of the Quantum Theory of Atoms in Molecules (QTAIM). Features of the covalent bonds demonstrate the presence of multiple bonds of various order. Strong intramolecular hydrogen bonds and weaker intermolecular bonds within the layer structure are characterized by the properties of their (3, −1) critical points. Weaker interactions, predominantly O···O, between the layers have additionally been characterized. Integrated atomic charges are also reported. The importance of correcting the primary X-ray data for λ/2 contamination is discussed.