B3LYP/DFT calculations of C5OH5 and C4O2H4 molecules

Abstract

This work include the study of five molecules. The density function theory at B3LYP  with 6-31G (d,p) was employed to calculate the effect of replacing oxygen atoms instead of the carbon in the benzene molecule on the electronic properties in two different ways: Koopmans and adiabatic. These properties included the total energy, electronic states, energy gap, ionization potential, electron affinity, electronegativity, hardness, softness and electrophilic index. As aresult note increase the overall energy with change the location of two oxygen atoms and the highest energy emerged in the molecule (1,2 O-C₄H₄), the molecule (1,2 O- C₄H₄) is more soft (S) with small energy gap (E_g) in comparison with benzene ,and it more electrophilicity (?) and more reactivity (?).