Probing the weakest bond and the cleavage of p-chlorobenzaldehyde diperoxide energetic molecule via quantum chemical calculations and theoretical charge density analysis

• Published in: International journal of quantum chemistry 2011-11, Vol.111 (14), p.3741-3754
• Main Authors: Stephen, A. David, Revathi, M., Asthana, S. N., Pawar, Rajesh B., Kumaradhas, P.
• Format: Article
• Language: English
• Subjects: AIM analysis; bond strength; electron distribution; energy density; topological parameters
• ISSN: 0020-7608; 1097-461X
• DOI: 10.1002/qua.22879

A high‐level ab initio Hartree‐Fock/Møller‐Plesset 2 and density functional theory quantum chemical calculations were performed on p‐chlorobenzaldehyde diperoxide energetic molecule to understand its bond topological, electrostatic, and energetic properties. The optimized molecular geometry for the basis set 6‐311G** exhibit chair diperoxide ring and planar aromatic side rings. Although the diperoxide ring bear same type of side rings, surprisingly, both the rings are almost perpendicular to each other, and the dihedral angle is 96.1°. The MP2 method predicts the OO bond distance as ∼1.466 Å. The charge density calculation reveals that the CC bonds of chlorobenzaldehyde ring have rich electron density and the value is ∼2.14 e Å−3. The maximum electron density of the OO bonds does not lie along the internuclear axes; in view of this, a feeble density is noticed in the ring plane. The high negative values of laplacian of CC bonds (approximately −22.4 e Å−5) indicate the solidarity of these bonds, whereas it is found too small (approximately −1.8 e Å−5 for MP2 calculation) in OO bonds that shows the existence of high degree of bond charge depletion. The energy density in all the CC bonds are found to be uniform. A high electronegative potential region is found at the diperoxide ring which is expected to be a nucleophilic attack area. Among the bonds, the OO bond charge is highly depleted and it also has high bond kinetic energy density; in consequence of this, the molecular cleavage is expected to happen across these bonds when the material expose to any external stimuli such as heat or pressure treatment. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011