We present results from the application of a computational package Selection of Semiconductor Composition for Photoelectrochemical Solar Cells (SSCPECS) developed to assist in the selection of stoichiometric compounds of mixed materials and the best mixing ratio for narrowing the extent of further experimental investigations. These calculations can provide an estimate of the mixing ratio for obtaining a desired band gap and thereby assist in developing appropriate electrodes for photovoltaic (dry and wet) solar cells. The package has been applied to 28 different semiconductors and insulators. Applications to mixed oxide semiconductor systems PbO2-TiO2 and PbO-SnO establish its applicability for the purpose mentioned above. The computer program is based on the Charge-Self-Consistent Band Structure (CSCBS) method and the calculated band gaps for pure and mixed semiconductors are quite reasonable. The software package is available on request.