Semire, Banjo Ladoke Akintola University of Technology - Department of Pure and Applied Chemistry, Nigeria , Odunola, Olusegun Ayobami Ladoke Akintola University of Technology - Department of Pure and Applied Chemistry, Nigeria

THEORETICAL STUDY ON STRUCTURE AND ELECTRONIC PROPERTIES OF 4H-CYCLOPENTA[2,1-B,3;4-B’]DITHIOPENE S-OXIDE AND ITS CCL2 AND CF2 BRIDGED DERIVATIVES

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Quantum chemical calculations using semi-empirical, ab initio, density functional theory (DFT) and Møller plesset (MP2) methods were performed on 4H-Cyclopenta[2,1-b,3;4-b’]dithiopene S-oxide derivatives (i.e. bridged dithiophene S-oxides, BTOs). The geometries, stabilities, electronic and thermodynamic properties of the compounds were studied. The thermodynamic parameters calculated at PM3 were in good agreement with those calculated at B3LYP/6-31G(d) level. The band gap energies calculated at B3LYP/6-31G(d) level for the BTOs were lower than the un-substituted trithiophene but higher than 4H-Cyclopenta[2,1-b,3;4-b’]dithiopene (Bouzzine, 2005). The absorption λmax calculated using TD-DFT was shifted to longer wavelength by successive replacement of methylene hydrogens of BTO by chlorine and fluorine atoms.

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electronic properties , bridged dithiophene S , oxides , theoretical methods

Lebanese Science Journal

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