The initial steps of photosynthesis require the absorption and subsequent transfer of energy through an intricate network of pigment–protein complexes. Held within the protein scaffold of these complexes, chromophore molecules are densely packed and fixed in specific geometries relative to one another resulting in Coulombic coupling. Excitation energy transfer through these systems can be accom...

Recent work has revealed the first observation of stereochemical effects on intervalence charge transfer (IVCT) in diand trinuclear mixed-valence complexes. The differential IVCT characteristics of the diastereoisomers of polypyridyl complexes of ruthenium and osmium offer a new and intimate probe of the fundamental factors that govern the extent of electronic delocalization and the barrier to ...

Aimed at creating a true photoswitchable energy transfer system, four dinuclear complexes containing ruthenium(II) and osmium(II) metal centers bridged by spiropyran-type linkers were designed and investigated. The bridge in its closed spiropyran form was shown to be a good insulator for energy transfer between the Ru-bpy donor and the Os-bpy acceptor (bpy = 2,2'-bipyridine). On the basis of pr...

Guanine nucleotide binding protein (G protein)-coupled receptors (GPCRs) function in complexes with a range of molecules and proteins including ligands, G proteins, arrestins, ubiquitin, and other receptors. Elements of these complexes may interact constitutively or dynamically, dependent upon factors such as ligand binding, phosphorylation, and dephosphorylation. They may also be allostericall...