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To develop efficient sensitizers, five novel metal‐free dyes were designed based on one of the best dyes W05 by inserting auxiliary electron acceptors. The photovoltaic performance of new dyes was studied by density functional theory (DFT) and time‐dependent DFT (TDDFT) calculations in order to shed light on how the auxiliary electron acceptor influences on the photovoltaic performances. Results illustrated that the insertion of auxiliary electron acceptors can narrow the HOMO‐LUMO gap, red‐shift the light absorption band, and enhance the sunlight harvesting. By estimating three important photovoltaic parameters, the photoelectric conversion efficiency (PCE) of W05 was estimated to be about 8.96%, in good agreement with its experimental value of 9.22%, indicating that the scheme calculated the photovoltaic parameters is reliable. Interestingly, the estimated PCE values for designed dyes are superior to that of W05, suggesting that the molecular design is reasonable. Especially 5, its PCE was predicted to be as high as 14.07%, indicating that 5 is a promising sensitizer candidate for DSSC applications. [ABSTRACT FROM AUTHOR]

The clusters Tl x O (x = 2–4) were studied using density functional theory (B3PW91). The global minima contain linear di-coordinated, T-shaped, tri-coordinated and square-planar tetra-coordinated oxygen for Tl 2 O, Tl 3 O and Tl 4 O, respectively. The 18-valence electron rule and the preference for planar structure for Tl 4 contribute to square structure for Tl 4 O. The NICS values reveal that the σ and π double aromaticity (especially π aromaticity) contributes to stabilizing the planar tetra-coordinated bonding of oxygen. In addition, the trend in stability of n-coordinated oxygen structures are found to be in the following order: 4 > 3 > 2 > 1. [ABSTRACT FROM AUTHOR]

In the current work, dependent density functional theory and time-dependent density functional theory calculations coupled with the inherent charge hopping model and some visualization techniques have been used to systematically investigate the photovoltaic properties of PC61BM-PDPP5T system. Calculations show that PC61BM-PDPP5T system possesses the relatively large open-circuit voltage 0.82 V the middle-sized exciton binding energy (0.690 eV), the small internal reorganization energy (0.159 eV) in the exciton-dissociation process, but the relatively large one (0.396 eV) in the case of charge-recombination. With a simplified molecular model, the exciton-dissociation rate constant, kdis, is estimated to be as large as 1.156 × 1010 s−1 in PC61BM-PDPP5T phase interface, while the charge-recombination one, krec, is only 1.018 × 107 s−1 under the same condition, which indicates a rapid and efficient photoinduced exciton-dissociation process. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The title compound, [Mn(C7H3NO4)(C12H6N2O2)(H2O)2]·2H2O, is a neutral mononuclear MnII complex. The Mn—N bond to the pyridine-2,6-dicarboxylate ligand lies along a crystallographic twofold rotation axis. The Mn2+ cation has a distorted pentagonal–bipyramidal configuration, coordinated by three N atoms, one from the pyridine-2,6-dicarboxylate ligand and two from the chelating 1,10-phenanthroline-5,6-dione ligand. The remaining four coordination sites are occupied by O atoms, two from the pyridine-2,6-dicarboxylate ligand and two from water molecules. The asymmetric unit also contains a solvent water molecule. The crystal structure is stabilized by a network of O—H...O hydrogen-bonding interactions in a three-dimensional supramolecular structure. [ABSTRACT FROM AUTHOR]