Study the Effect of Hydroxyl Radical on the Monogermacyclobutane Molecule by using Density Functional Theory

This work reports a theoretical study to investigate the electronic structure and optimized geometry for a saturated molecules group by using density functional theory (DFT) at B3LYP level with bases set 6-31G. Cyclobutane molecule is an original molecule before substitute one-carbon atom by one-germanium atom. The effect of substitute on cyclobutane molecule is discussed on the basis of the calculated electronic properties. The electronic properties included total energy, energy gap, ionization potential, electronic affinity, hardness and softness, which have been found with varying differences for each molecule, with comprehensive analysis of the calculated highest-occupied and lowest-unoccupied orbital (HOMO and LUMO respectively) energies. These properties also studied with substituting the one hydrogen atom by one hydroxyl (OH) radical in same molecular. The results in this study show that the calculated total energy, energy gap and ionization potential for cyclobutane have been found a good agreement with the previous studies. For other molecules, we have not found a reference data, so this study supplies a new data in this aspect. These calculations have been performed using Gaussian 03 package. Keywords: Cyclobutane, DFT, energy gap, ionization potential