B3LYP/6-311G(d,p) quantum calculations are performed to optimize geometries and obtain properties depending on the electronic, optical and photovoltaic parameters for some pyridazine derivatives. These novels four organic donor-π-acceptor dyes (D-π-A) used for dye-sensitized solar cells (DSSC). The results have shown that the polarizable continuum model (PCM) were reasonably capable of predicting the excitation energies, the absorption and the emission spectra of the molecules. The HOMO and LUMO energy levels of these dyes can ensure a positive effect on the process of electron injection and dye regeneration. Gaps energy ΔEg, short-circuit current density (Jsc), light-harvesting efficiency (LHE), injection driving force (ΔGinject), total reorganization energy (λtotal) and opencircuit photovoltage (Voc) permit qualitative predictions about the reactivity of these derivatives.
