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Benzophenone derivatives (BZP), an important class oforganic UV filters, are widely used in sunscreen products due to theirability to absorb in the UVA and UVB ranges. The structural, electronic,and spectral properties of BZP derivatives have been studied by densityfunctional theory (DFT) and time-dependent DFT (TD-DFT) methods. DFT/B3LYPwith the 6-31G(d) basis set is an accurate method for optimizing thegeometry of BZPs. The absorption maxima obtained from the TD-DFT calculationsin a vacuum were in agreement with the experimental absorption bandsand showed that the main electronic transitions in the UVA/UVB rangepresent π → π* character, the major transitionbeing HOMO → LUMO. The oscillator strength seems to increasein the presence of disubstitution at the para position. For proticsubstituents, the position appears to be related to the absorptionband. Absorption in the UVB range occurs in the presence of para substitution,whereas ortho substitution leads to absorption in the UVA spectralregion. The obtained results provide some features for BZP derivativesthat can be useful for customizing absorption properties (wavelengthsand intensities) and designing new BZP derivatives as sunscreens. [ABSTRACT FROM AUTHOR]