Computational and experimental research has shown that tautomer equilibrium greatly depends on the solvent medium. Using Gaussian03, the optimized geometries of the diketo and enolone forms of acetylacetone were obtained using a hybrid density functional model and a polarization basis set with diffuse functions on both the heavy atoms and hydrogen (B3LYP/6-311++G**). Geometry optimizations within a given solvent (CCl4 and methanol) were performed and the effects of using a modified Bondi solvation model to approximate the solvent-solute interactions were examined. The medium used to examine the accuracy of different solvation models was 1H and 13C NMR spectra of acetylacetone. Using Gaussian03, 1H and 13C chemical shift data for the acetylacetone tautomers (using B3LYP/6-311++G(2d,p) methods), which allowed the effects of solvation models to be compared to experimental 1H and 13C NMR spectra.