Effect of some Substituents on the Optimization And Electronic Properties of Cyclopentane and Di-Cyclopentane.


This work reports a theoretical study to investigate the best geometric optimization and electronic structure for cyclopentane and di-cyclopentane molecules by using density functional theory (DFT) at B3LYP level with basis set 6-31G. Cyclopentane molecule is original molecule before replacing the carbon atoms by nitrogen and oxygen atoms. The effect of substitute on cyclopentane and di-cyclopentane molecules discussed based on the calculate of optimization parameters and the electronic properties. The electronic properties which included total energy, energy gap, ionization potential, electronic affinity, chemical potential, hardness, charge transfer, softness, electronegativity and electrophilicity, have been found with varying differences for each molecule. In this work we found some of these properties (energy gap, total energy and hardness) increasing after replacing C atom by N and O atoms and (C4H5N) considered from insulation materials and more hardness than studied molecules because it has larger magnitude from energy gap and hardness, in addition to this molecule less affinity with the physical medium, while (C8H5NO) more affinity with the physical medium that makes it more stability comparing with other molecules. Calculations are carried out by employing the Gaussian 09 package of program.