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Hi, This week's CORE-CM seminar is, Thursday Oct. 24: Elena Jakubikova (Chemistry, North Carolina State University) "Earth abundant solar cells: Can iron complexes serve as photosensitizers in DSSCs " BPS 1400 at 12:00pm Pizza and cookies at 11:45AM The abstract is below Phil Photoactive transition metal complexes anchored to semiconductor surfaces play an important role as chromophores in artificial systems for solar energy conversion, such as dye-sensitized solar cells (DSSCs). Fe(II)-polypyridines share many properties with Ru(II)-polypyridines, which have been successfully used as photosensitizers in DSSCs. Visible light excitation in both types of compounds results in the population of photoactive metal-to-ligand charge transfer states (MLCT). The main obstacle to the utilization of Fe(II)-based compounds as photosensitizers is the short lifetime of the initially populated MLCT states due to their de-activation by ultrafast intersystem crossing events into photo-inactive metal centered (MC) ligand-field states. We employ density functional theory and quantum dynamics simulations to investigate how various modifications to the polypyridine ligands as well as semiconductor anchor groups influence the relative energies of the MC and MLCT states and relative rates of the intersystem crossing and interfacial electron transfer events. The results obtained lead to better understanding of structure-property relationships in these complexes and have implications for development of photosensitizers based on first-row transition metals.