The Predictive Accuracies of Spectroscopic Parameters in Biological Macromolecules by Fragment MO Method

The Fragment-Molecular-Orbital (FMO) method is an approximate quantum chemical method for huge systems like biological macromolecules and is known to provide not only an accurate total energy but also properties of the system with sufficient precision compared with conventional first principle methods. In the present study we report the spectroscopic properties such as dipole moment, polarizability and their derivatives by the FMO in order to examine the accuracy of the method in predicting IR and Raman spectroscopies of biological macromolecules. The results show the promising features of the method as a theoretical tool in the spectroscopic study of large bio-systems.