Molecular, vibrational (FT-IR and FT-Raman), NMR and UV spectral analysis of imidazo[1,2-b]pyridazine using experimental and DFT calculations

A combined experimental and theoretical study on molecular and vibrational structure of imidazo[1,2-b]pyridazine (IP) was carried out. In this work, molecular geometry and vibrational frequencies of IP in the ground state have been calculated using the density functional method, B3LYP/6-311++G (d,p) level. The vibrational spectra (FT-IR and FT-Raman) H-1 NMR, C-13 NMR and UV of IP have been experimentally recorded. The optimized geometry was in good agreement with the reported experimental values obtained from the X-ray crystal structure of IP in IP monohydrate. The scaled down vibrational frequencies calculated at 6-311++G(d,p) level correlated well with the experimental values. The theoretical spectrograms of FT-IR, FT-Raman, H-1 NMR, C-13 NMR and UV of the title compound have been constructed and compared with experimental spectra.