Abstract: Background: Conjugated systems are of great interest to chemists, particularly photochemists and spectroscopists. Benzophenone (BP), a highly conjugated compound is a well-known compound attracting keen interest from photochemist. Methodology: A comparative knowledge of the nature of ground state of dimethoxythiobenzophenone (DMTB) and dimethoxybenzophenone, their geometries, band gaps, absorption and transition properties will be a valuable contribution for further studies and practical applications. Results: The UV analysis of benzophenone (BP) in two solvents (ethanol, ε = 24.5 and n-hexane, ε = 1.88) and FT-IR correlated with Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TDDFT) of benzophenone (BP), thiobenzophenone (TBP), dimethoxybenzophenone (DMB) and dimethoxythiobenzophenone (DMTB) suggests a singlet ground state. Conclusion: The DMTB absorbs at the visible region with a lower band gap than DMB. The BP exhibits two bands: (I) A red shift from 247.6 nm (non-polar solvent) to 252.3 (polar solvent), Δλ = +4.7 nm and (II) A blue shift from 205.3 nm (non-polar solvent) to 197.7 nm (polar solvent), Δλ = -7.6 nm. This shows that band I is likely to be π→π* and band II n→π*. The DMB like BP absorbs at the UV region of the spectrum and unlike DMTB whose absorption is principally at the visible region. The DMTB showed a longer bond length of the thiocarbonyl (C=S) than carbonyl (C=O) in BP and DMB.