Molecular control of recombination dynamics in dye-sensitized nanocrystalline TiO2 films: Free energy vs distance dependence - Clifford, JN; Palomares, E; Nazeeruddin, MK; Grätzel, M; Nelson, J; Li, X; Long, NJ; Durrant, JR (JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2004)