Abstract

Theoretical study of molecular structure, conformations, and vibrational spectra for diazabicyclo [1.1.0]butane and diazabicyclo [2.1.0] pentane

Author(s): Rana Jamal, Shatha FadilAl-Saidi

The DFT[B3LYP/6-311G**(d,p)] theoretical study have been performed to calculate the total energies, optimized geometry, molecular orbitals, and vibrational spectra of the following molecules diazabicyclo[1.1.0]butane (DABCB), bicyclo[1.1.0]butane (BCB), diazabicyclo[2.1.0] pentane (DABCP), and bicyclo[2.1.0]pentane(BCP). A complete vibrational assignment was proposed. The structural parameters and puckering potential profiles were analyzed. The DABCB molecule possess twoconformations, themost stable form was the puckered which was 312.4 kJ mol-1 lower than the planar form. While the DABCP molecule had three conformations, it can be arranged according to their stability in the following order; envelop, twist, and planar.