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The structural and electronic properties of well-known 4,4′-(4-(5-(2,2-dicyanovinyl)thiophen-2-yl)phenylazanediyl)dibenzoic acid ( O2) and its hypothetical dyes O3- O7 were investigated by computational techniques. The absorption properties were probed. By replacing the 2-methylidenepropanedinitrile acceptor with 1,3-diethyl-5-methylene-2-thioxo-dihydropyrimidine-4,6(1 H,5 H)-dione, the molecular orbital energy levels were well tuned. The modified dyes meet the basic requirements of both -Δ Ginj and -Δ Greg being over 0.2 eV for an efficient hole injection and dye regeneration, respectively. All the designed p-type dyes O3- O7 have smaller energy gap and significant red shift in absorption spectra than that of the reference O2. Finally, our results suggested that O3- O7 have larger light-harvesting efficiencies (LHE) in the visible spectral regions of 400 nm to 700 nm than O2. Among all the dyes, O5 is expected to have an excellent performance as a p-type sensitized dye in solar cells due to its great LHE and sufficient hole injection efficiency. [ABSTRACT FROM AUTHOR]