Photo-induced charge transfer process between the carotenoids and (TiO2)(15b) was theoretically studied with quantum chemical methods, and the charge transfer information of the carotenoid-(TiO2)(15) complex were visualized using the charge difference density method. Calculated results show the strongest absorption wavelength is located at 606 nm. Electron transfer in the isolated (TiO2)(15) was also analyzed in some detail. For 15b (C-2v), electrons transfer from one layer to the other layer; while for 15a (C2v), electrons transfer from the outer O atoms to the inter Ti atom. (C) 2009 Elsevier B.V. All rights reserved.