In this work, we explore the geometries, relative stabilities, singlet-triplet (S-T) splittings, and local aromaticities of the 25 possible didehydrophenanthrenes (DDPs) at the BLYP/6-31G(d) level. The main aim is to understand their molecular structure and stability in terms of the electronic structure. To this end, we analyze the changes induced by didehydrogenation in molecular structure and...

Decays of individual rovibronic levels of trans-glyoxal in its first excited singlet state are investigated in supersonic-jet conditions. Several rotational levels display oscillatory decay from coherent excitation of superposition of singlet and triplet states. Analysis yields a lower bound for the state-dependent coupling matrix elements yST50.08– 62 MHz for the S1 – T1 interaction. These mat...

Intramolecular singlet fission (iSF) has shown potential to improve the power conversion efficiency in photovoltaic devices by promoting splitting of a photon-absorbing exciton into two triplet excitons within single molecule. Among different possibilities, donor–acceptor modular strategy copolymers great promise its ability undergo iSF under certain conditions. However, number reported literat...

The electronic structure and photophysics of the recently designed organic direct singlet harvesting (DSH) molecule are explored, in which donor (D) acceptor (A) held at distance by two bridges. One bridges is functionalized with fluorene. This leads to an ultrasmall singlet–triplet energy gap ?E (S1?T1) ? 10 cm?1 (?1 meV) between charge transfer states 1,3CT shows energetically close-lying 3??...

The reaction of molecular oxygen with palladium(0) centers is a key step in Pd-catalyzed aerobic oxidation reactions. The present study provides a density functional theory (DFT) computational analysis of the mechanism and electronic structural features of the reversible, associative exchange between O(2) and ethylene at an ethylenediamine (en)-coordinated palladium(0) center. Salient features ...

Electron-pair intracule (relative motion) and extracule (center-of-mass motion) densities are studied in both position and momentum spaces for the difference in the intracule densities shows that the probability of a small interelectronic distance is larger in the triplet for all the six atoms, as reported for the lightest Be atom in the literature. The position-space extracule density clarifie...

The character of singlet (C(3)N(2)H(5))CuO(2) ranges smoothly between copper(III) peroxide and copper(II) superoxide with variation of the electronic character of the supporting beta-diketiminate ligand. Over the range of the variation, multireference second-order perturbation theory predicts the (1)A(1) singlet state always to be lower in energy than the lowest triplet state ((3)B(1)). The mul...

für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...

Introduction. The photobleaching, or reduction in fluorescence quantum yield, of fluorescent dyes upon continuous excitation is a commonly encountered problem. The mechanism of photobleaching in fluorescent dyes has been shown to be complex, sensitive to environmental and excitation conditions, and specific to each dye. Nevertheless, two primary pathways are invoked to explain the photodegradat...

The iron oxide dimers (FeO)2 and their peroxide isomers are studied with the B3LYP density functional as bare clusters and as hexacarbonyls. Among the bare clusters the planar four-member ring structures are more stable than the non-planar ones and the rhombic dioxide Fe2O2 with antiferromagnetically ordered electrons on iron centers is the global minimum. Water adsorption on the bare diiron di...