Computation of the conventional strain energy in oxaziridine

Abstract

The conventional strain energy for oxaziridine is determined within the isodesmic, homodesmotic, and hyperhomodesmotic models. Using these models, the conventional strain energy for cyclopropane, cyclobutane, cyclopentane, and cyclohexane are also computed for comparison purposes. Optimum equilibrium geometries, harmonic vibrational frequencies, and corresponding electronic energies are computed for all pertinent molecular systems using SCF theory, second-order perturbation theory, and density functional theory and employing two basis sets of triple-zeta valence quality: 6-311G(d,p) and 6-311+G(2df,2pd). Single-point fourth-order perturbation theory and CCSD(T) calculations employing the larger basis set are also computed at the MP2/6-311+G(2df,2pd) optimized geometries to determine the effect of higher-order correlation effects on ring strain computation. Finally, the ring strain of oxaziridine is compared to other small ring systems.