Theoretical investigation of the conformation for 2-butanimine

Abstract

The molecular structure and conformational stability of 2-butanimine have been investigated using ab initio and density functional theory methods. The molecular geometries for various conforms are optimized employing MP2, BLYP, and B3LYP methods implementing 6-311++G ∗∗ basis sets. From the calculations, the molecules are predicated to exist in four stable conformers with the (E)-sp form being slightly lowers in energy than the other ones. The vibrational frequencies for the four conforms are computed at different levels and compared to the fundamental values. The results indicate that B3LYP frequencies reproduce the experimental values satisfactorily. On the basis of the comparison between calculated and experimental results, the fundamental vibrational modes are assigned. Through the analysis of the vibrational modes and frequencies for the four conformers, we can conclude that the vibrational quantum number ν is a crucial variable to get reasonable energy difference between various conformations.