DENSITY FUNCTIONAL THEORY CALCULATIONS OF VIBRATIONAL SPECTRA OF THIOSEMICARBAZONE OF ACETONE AND ACETALDEHYDE
C. JEEVARATHINAM *
Department of Chemistry, AAGAS College, Karaikal, Puducherry State, India.
G. V. PANDIAN
Department of Chemistry, T.B.M.L College, Porayar, Tamil Nadu, India.
M. GOVINDARAJAN
Department of Physics, AGCW College, Karaikal, Puducherry State, India and Department of Physics, AAGAS College, Karaikal, Puducherry State, India.
*Author to whom correspondence should be addressed.
Abstract
In this work, the experimental and theoretical vibrational spectra of thiosemicarbazone of acetone and acetaldehyde were studied. FT-IR and FT-Raman spectra of compounds were recorded in the region 4000–400 cm-1 and 3500–50 cm-1, respectively. The structural and spectroscopic data of the molecules were calculated by using density functional method (B3LYP) with the 6-311++G(d, p) basis set. The vibrational wavenumbers were calculated and scaled values were compared with experimental FT-IR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The optimized geometric parameters (bond lengths and bond angles) were compared between values of thiosemicarbazone of acetone and acetaldehyde.
Keywords: Infrared, Raman, DFT, B3LYP, acetone and acetaldehyde.