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This study investigated the therapeutic activity of a series of chain thiophene photosensitizers (PS) using theoretical simulation approaches. Density functional theory and its time-dependent extension (DFT, TD-DFT) were used to calculate the parameters for the determination of various photophysical properties of PSs, such as electronic absorption spectrum, singlet-triplet state energy gap, and to discuss the electron-hole relationship between excited states and orbitals. The calculations show that these photosensitizers have a practical inter-system crossing (ISC) transition from the first singlet excited state to the lower triplet state excited state with sufficient energy to produce reactive oxygen species (ROS). These suitable properties make these series of PSs promising for photodynamic therapy (PDT) applications. these photosensitizer molecules in this work can provide a theoretical reference for further experimental researches.

A series of blue phosphorescent heteroleptic cyclometalated Ir(III) complexes with mesitylphenyl-imidazole ligands for organic light-emitting devices have been theoretically studied. We want to find their electronic structures, spectroscopic properties, and application value for organic light-emitting devices. (fppz)2Ir(acac), (fppz)2Ir(tpip), (dfbdp)2Ir(fppz), (F-fppz)2Ir(acac), (F-fppz)2Ir(tpip), and (dfbdp)2Ir(F-fppz) are investigated with DFT and TD-DFT approaches, where, for (fppz)2Ir(acac), (fppz denotes 2-(5-(trifluoromethyl)-4H-pyrazol-3-yl)pyridine, and acac denotes acetylacetonate); for (fppz)2Ir(tpip), tpip denotes tetraphenylimido-diphosphinate; and, for (F-fppz)2Ir(acac) and (F-fppz)2Ir(tpip), F-fppz denotes 2-(5-fluoro-4H-pyrazol-3-yl)pyridine.

An effective improvement on the empirical orthogonal function (EOF)–based bias correction method for seasonal forecasts is proposed in this paper, by introducing a stepwise regression method into the process of EOF time series correction. Using 30-year (1981–2010) hindcast results from IAP AGCM4.1 (the latest version of this model), the improved method is validated for the prediction of summer (June–July–August) rainfall anomalies in Southeast China. The results in terms of the pattern correction coefficient (PCC) of rainfall anomalies shows that the 30-year-averaged prediction skill improves from 0.01 to 0.06 with the original correction method, and to 0.29 using the improved method. The applicability in real-time prediction is also investigated, using 2016 summer rainfall prediction as a test case. With a PCC of 0.59, the authors find that the new correction method significantly improves the prediction skill; the PCC using the direct prediction of the model is −0.04, and using the old bias correction method it is 0.37.

As an important precursor, the dinuclear [{Ir(C^N)2Cl}2] (C^N = ppy, dfppy) derived luminescent complex is nearly non-emissive at room temperature, but two similar chlorine-bridged dinuclear complexes [{Ir(ppy)2}2Cl(BTA)] (1) and [{Ir(dfppy)2}2Cl(BTA)] (2) (BTA = 1,2,3-benzotriazole) are proved to be bright. Herein, we report both complexes 1 and 2 from the viewpoint of experiment and theory. In order to characterize the two complexes better, single-crystal X-ray diffraction of 1 and 2 was carried out to determine their molecular structure. The emission spectra at room temperature (298 K) was measured, and the emission quantum yields for 1 and 2 in degassed CH2Cl2 were also given. The combined density functional theory (DFT) and time-dependent DFT (TDDFT) study was employed to gain insights into the electronic structure and radiative decay of these systems.