Fast Approaches for Molecular Polarizability Calculations

Molecular polarizability of a molecule characterizes the capability of its electronic system to be distorted by
the external field, and it plays an important role in modeling many molecular properties and biological activities.
In this paper, a set of fast empirical models have been developed to predict molecular polarizability using
two types of approaches. The first type of approaches is based on Slater's rules of calculating the effective
atomic nuclear shielding constants. The best model (model 1A) of this category has achieved an average
unsigned error (AUE), root-mean square error (RMSE), and average percent error (APE) of 2.23 au, 3.29 au,
and 2.77%, respectively. The second type of model is based on an additive hypothesis of molecular
polarizability. Five models have been constructed using different schemes of atom types. The best model that
applies 14 atom types, model 2e, achieves AUE, RMSE, and APE of 0.99 au, 1.48 au, and 1.24%, respectively.
This performance is much better than those of the models purely based upon chemical composition (model
2A and the Bosque and Sales model), for which errors are about 2-fold higher. It is expected that both model
1A and model 2E will have broad applications in QSAR and QSPR studies.