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Hydrogen peroxide (H2O2) as relatively stable reactive oxygen species gains considerable attention because it can regulate physiological and pathological processes. In order to better detect H2O2, fluorescent probes were widely applied. Over the past 20 years, a great deal of boronate‐based fluorescent molecular probes appeared due to relatively simple oxidation reaction. However, the reaction mechanisms that boronate derivatives were converted into fluorescent product by H2O2 are poorly studied. In this paper, taking coumarin‐7‐pinacolboronate (CBU) as an example, the oxidation mechanism of boronate‐based probes by various reactive oxygen species was studied by theoretical calculations. The results found that (1) the chemical reaction mechanisms are nearly identical for the reactions of CBU with hydrogen peroxide, hypochlorous acid, peroxynitrite, and tyrosine hydroperoxide, respectively. (2) There is not radical intermediate during the reaction. (3) The different reactive oxygen species has a strong influence on rate limiting step and reaction rate. [ABSTRACT FROM AUTHOR]

Single atom catalysts had been widely used in oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). However, the relationship between local coordination environment and catalytic activity were unclear. In this work, the effect of N‐defect and axial halogen atoms on electrocatalytic OER/ORR activity of FeN4 catalysts were investigated by density functional theory calculations (DFT). When the overpotential was the only criterion, FeN3Br was the optimal candidates for OER, followed by FeN3F, FeN4I, FeN4Cl and FeN4Br; FeN4I, FeN4Br and FeN4Cl were also the promising candidates for ORR. FeN4I, FeN4Br and FeN4Cl may be excellent ORR catalysts in an acidic media because of the low overpotential and reaction barrier of kinetics rate limiting step. In summary, N‐defect and axial halogen atoms can effectively balance kinetics, thermodynamics and catalytic activity. [ABSTRACT FROM AUTHOR]

It has been proved that triphenylamine (TPA) derivatives can be excellent candidates for hole-transporting materials in organic light-emitting diodes (OLEDs). To improve on the thermal and morphological stability, a fully diarymethylene-bridged TPA derivative (FATPA) which has been proven to enhance electroluminescent (EL) efficiency was synthesized. On the basis of FATPA, two series of novel bridged TPA derivatives have been designed by using diarylmethylene (Series A) or dimethyfluorene (Series B) as the linkage between the ortho-positions of the phenyl rings in this work (see Fig. 1). To reveal the relationships between electronic structures and photophysical properties of these novel functional materials, an in-depth theoretical investigation was elaborated via quantum chemical calculations using the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods. In addition, the feasibility of using these bridged TPA derivatives as host in the device of ITO/MoO3/NPB/mCP/host:Ir(ppy)3/TAZ/LiF/Al was also evaluated, which including the discussion to their energy levels match with adjacent layers and energy transfer from host to guest. These calculated results show that photophysical properties can be easily tuned by the introduction of various substituent groups into the bridged TPA derivatives, such as the highest occupied molecular orbitals (HOMOs), the lowest unoccupied molecular orbitals (LUMOs), the energies difference between the HOMOs and LUMOs (ΔH-L), the lowest singlet ( ES) and triplet ( ET) excitation energies, ionization potentials (IPs), electron affinities (EAs), reorganization energies (λ) and the absorption and emission spectra, indicating that these bridged TPA derivatives have great potential applications for OLEDs. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 [ABSTRACT FROM AUTHOR]

In the title compound, [Mn(C(7)H(2)F(3)O(3))(2)(C(10)H(8)N(2))(2)(H(2)O)(2)], the Mn(II) ion, situated on a centre of inversion, has a distorted octa-hedral coordination geometry and is coordinated by two N atoms from two 4,4'-bipyridine ligands, two O atoms from two 2,4,5-trifluoro-3-hy-droxy-benzoate ligands and two water mol-ecules. Inter-molecular O-H⋯N hydrogen bonds link the mol-ecules into a chain along the a axis. Inter-actions between neighboring chains occur through O-H⋯O hydrogen bonds, which link the chains into a two-dimensional supra-molecular network parallel to the ac plane. In addition, O-H⋯O hydrogen bonds between the water mol-ecules and carboxyl-ate groups also exist in the the crystal structure.