Ab initio Study of Tri ethyl Phosphine Oxide Stability and its Calcogenides

The molecular geometries of (CH3CH2)3P=X , (X=O,S,Se) were fully optimized using the gradient minimization technique in different solvents the computed geometrical parameteres at the HF/6-31G* level of theory corresponds well to those determined experimentally by X-ray and ED diffraction. The relative stability of these molecules were investigated at the Hartery-Fock method and 6-31G* basis set in toluene, chloroform, dichloroethane, dicloromethane, acetone, ethanol, methanol, DMSO and benzene as solvents. The results are summerized in the table and shows these molecules are more stable in polar solvents rather than nonpolar solvens.