Computational prediction of relative group polarizabilities



Earlier work has shown that molecular polarizabilities correlate well with the quantity V/IS,ave, where V is the volume of the molecule and IS,ave is the average value of the local ionization energy on its surface. We now extend this to group polarizabilities; we computed V/IS,ave for four common chemical groups (NO2, CH3, NH2, and OH) in a variety of molecules. The transferabilities of IS,ave, V, and V/IS,ave are examined, as well as the correlation between V/IS,ave and literature polarizabilities of CH3, NH2, and OH. This permits the value for NO2 to be predicted (α = 2.77 Å3). The dependence of IS,ave, and therefore V/IS,ave, upon the remainder of the molecule is discussed. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003