Determination of parameters for vibration and molecular structures of some major importand donor via DFT method in biology

This work, consists of the accounts of vibrational frequencies (Infared and Raman) using 4,4?-dipyridylmonosulfide and 4,4'-dipyridyldisulfide molecules with the help of the program Gaussian 03W and with the methods and gen B3LYP/6-311+g(d,p) and MPW1PW91/dgdzvp by optimizing the structural parameters (the length of the connections, connection angle) of those determined molecules (at the lowest energy level) . The structural parameters and frequencies that we gain theoretically are compared with the experimental structural parameters and frequencies.