In this work, we make use of a model chemistry within Density Functional Theory (DFT) recently presented, which is called CHIH-DFT, to calculate the molecular structure of acenaphto[1,2-c]-1,2,5-thiadiazole 1,1-dioxide (Tacenaphto), as well to predict its infrared (IR) and ultraviolet (UV–vis) spectra, the dipole moment and polarizability, and the chemical reactivity parameters that arise from Con-ceptual DFT. The calculated values are compared with the experimental data available for this molecule as a means of validation of our proposed model chemistry.