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Improving Performance in Colloidal Quantum Dot Solar Cells by Tuning Band Alignment through Surface Dipole Moments
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Observation and Exploitation of Spin–Orbit Excited Dipole-Bound States in Ion–Molecule Clusters
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Orientational Dynamics of Transition Dipoles and Exciton Relaxation in LH2 from Ultrafast Two-Dimensional Anisotropy
Light-harvesting complexes in photosynthetic organisms display fast and efficient energy transfer dynamics, which depend critically on the electronic structure of the coupled chromophores within the complexes and their interactions with their environment. We present ultrafast anisotropy dynamics, resolved in both time and frequency, of the transmembrane light-harvesting complex LH2 from Rhodobacter sphaeroides in its native membrane environment using polarization-controlled two-dimensional electronic spectroscopy. Time-dependent anisotropy obtained from both experiment and modified Redfield simulation reveals an orientational preference for excited state absorption and an ultrafast equilibration within the B850 band in LH2. This ultrafast equilibration is favorable for subsequent energy transfer toward the reaction center. Our results also show a dynamic difference in excited state absorption anisotropy between the directly excited B850 population and the population that is initially excited at 800 nm, suggesting absorption from B850 states to higher-lying excited states following energy transfer from B850*. Finally, these results give insight into the ultrafast dynamics of bacterial light harvesting and the excited state energy landscape of LH2 in the native membrane environment.
Polarizable Anionic Sublattices Can Screen Molecular Dipoles in Noncentrosymmetric Inorganic–Organic Hybrids
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Controlling Ligand Excimer Formation with Dipole Changes in Emissive Rare-Earth/Phosphonic Acid Complexes
The interactions between substituted arylvinyl phosphonic acid (AVPA) ligands within a Eu-AVPA complex are shown to influence the outcomes of excited state evolution after photoexcitation. Compared with unfunctionalized AVPAs, pairs of ligands functionalized with CF 3 in the para position preassociate in the ground state of complexes with Eu 3+ according to calculated geometry optimizations. The CF 3 -substituted AVPA complexes show evidence of red-shifted optical absorption and undergo more efficient excimer formation, as revealed by transient absorption spectroscopy. We rationalize this behavior through simulations of excited-state geometry optimizations that reveal evolution toward interligand phenyl-phenyl planarity for specific excited states. Emission from complexed Eu 3+ after energy transfer from the ligand is found to be weaker with CF 3 substitution, which we hypothesize is due to intracomplex, interligand aggregates with excimer-promoting geometries. These observations point to the need to consider ground-state geometries as well as dynamic excited-state processes to understand the flow of energy in rare earth coordination complexes.
Modeling the Chiral Imprinting Response of Oriented Dipole Moments on Metal Nanostructures
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Noncollinear Electric Dipoles in a Polar Chiral Phase of CsSnBr 3 Perovskite
Not Available
Reinforcing Supramolecular Bonding with Magnetic Dipole Interactions to Assemble Dynamic Nanoparticle Superlattices
Abstract not provided
Helical Peptides Design for Molecular Dipoles Functionalization of Wide Band Gap Oxides
Not provided.