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• The potential energy curve of electronic states have been estimated for the (2) 3 Π − X 3 Π transition of GeC molecule using RKR method. • The radiative transition parameters have been estimated for the (2) 3 Π − X 3 Π transition of GeC molecule. • The effective vibrational temperature helps to ascertain the presence of GeC molecule in sunspot atmosphere. In this work, the experimental potential energy curves for (2) 3 Π and X 3 Π electronic states of GeC molecule have been constructed by using Rydberg-Klein-Rees (RKR) method. The radiative transition parameters viz., Franck-Condon (FC) factor, r-centroid, electronic transition moment, band strength, relative band strength, Einstein coefficients, radiative lifetime and oscillator strength for the (2) 3 Π − X 3 Π system of GeC molecule have been estimated for the experimentally observed vibrational levels from Rydberg-Klein-Rees (RKR) potential and the estimated values are tabulated. The estimated effective vibrational temperature found as 5628 K for the (2) 3 Π − X 3 Π system of GeC molecule. The radiative transition parameters and effective vibrational temperature are evident that the possible presence of GeC molecule in solar and sunspots atmosphere. Further, these parameters are employed in rationalizations of astrochemical and astrophysical observations. [ABSTRACT FROM AUTHOR]

[Display omitted] • There are smaller energy gap, larger SOC and more limited geometric structure changes in solid-phase environment. • The effective ISC and RISC processes between S 1 and T 2 reveal the TADF mechanism of PyB-DPAC. • The superior AIE property benefits from the suppressed non-radiative process and enhanced radiative transition. An investigation of high-performance organic green thermally activated delayed fluorescence (TADF) material, PyB-DPAC, with aggregation-induced luminescence (AIE) characteristics was theoretically conducted by the first principle calculations method in this work. The polarizable continuum mode (PCM) and the combination of quantum mechanics and molecular mechanics (QM/MM) method were employed to consider the liquid-phase and solid-phase environments, respectively. Results show that TADF mechanism of the molecule is mainly due to the occurrence of efficient intersystem crossing (ISC) and reverse intersystem crossing (RISC) processes between S 1 and T 2 , which benefits from the small energy gap, large SOC and the limited changes of molecular geometry structures in solid-phase environment. The increase of radiative transition rate (K r) and significant decrease of non-radiative transition rate (K nr) is responsible for the AIE property. Our calculations reasonably explained the experimental results and showed that PyB-DPAC is an excellent TADF material with AIE characteristics, this may help to better understand the influence of solid-state effect and the luminescence mechanism of AIE-TADF molecules. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) Y2Ti2O7 (YTO): Ho3+/Yb3+ nanofibers with diameters ranging from 300 to 400 nm were synthesized by an electrospinning technology and the structure of YTO nanofibers was identified as face-centered cubic pyrochlores. The detected green and red signals in the upconversion emission spectra under 980 nm laser excitation are due to the radiative transitions (5F4, 5S2) ? 5I8 and 5F5 = 5I8 of Ho3+ ions, respectively. YTO: Ho3+/Yb3+ nanofibers have the characteristics of porosity, threedimensional braidability, high specific surface area and controllable structure, which improves the performance of optical temperature sensing. Furthermore, the nanofiber membranes consisting of YTO: Ho3+/Yb3+ with temperature sensing performance can work steadily at medium temperature range in view of its fast responses and high stability, moreover, a maximum sensitivity about 0.18% K-1 at 423 K, which indicates that the nanofibers have good thermal sensitivity. 1D nanostructure rare earth iondoped cubic pyrochlore material was proven to obtain excellent upconversion luminescence properties, which provides a new route for the development of sensitive optical temperature-sensing materials. [ABSTRACT FROM AUTHOR]

• As yet, experimentally unknown cationic species: ScS+. • Reliable characterization of excited electronic states. • Transition moments, transition probabilities, radiative lifetimes. • Should help plan and guide future experimental investigations. High-level CASSCF/MRCI calculations with cc-pV5Z basis sets were employed to characterize a manifold of electronic states of the monosulfide cation ScS+ correlating with the three-lowest dissociation channels. The global energetic picture provided by the potential energy curves makes evident a region, especially above 35,000 cm−1, of high density of electronic states that presents a challenge for both experimentalists and computational chemists to assign properly the electronic transitions. For the lowest-lying singlet and triplet states, a whole set of spectroscopic parameters are provided. Additionally, data on dipole moment functions, transition dipole moment functions, radiative transition probabilities and lifetimes are also evaluated for a subset of singlet states, namely, X 1Σ+, B 1Π, C 1Π, G 1Σ+, H 1Π, I 1Π, and J 1Σ+, for which we identified favorable transitions to be investigated experimentally. Our results are sufficiently accurate and reliable to guide and motivate spectroscopists to investigate further this species. [ABSTRACT FROM AUTHOR]

In this study, we investigated the deep (semiinfinite) soil contribution to the brightness temperature at 1.4 GHz calculated through a modified incoherent radiative transfer model. We reproduced the measured brightness temperature collected by a dual L-band radiometer in a bare agricultural field. We found that exclusion of a semi-infinite soil layer in the incoherent model significantly decreased the brightness temperature when the measurement depth in the model was closer to the emitting depth, which is the first few centimeters from the top of soil. The maximum brightness temperature differences between the cases with and without the semi-infinite layer in the incoherent model were computed to be 6.8444 K, 2.8891 K, 0.2477 K and 0.0004 K for the measurement depths of 4 cm, 5 cm, 8 cm and 16 cm, respectively. Based on a comparison with another coherent radiative transfer model, we observed that inclusion of the deep soil layer significantly improved the precision of the incoherent model regardless of the measurement depth. Our results could be one example of improving the accuracy of radiative transfer models, which might be applied to other radiative transfer models and increase the precision of soil moisture retrieval calculations. [ABSTRACT FROM AUTHOR]

• CdS film's resistivity from 102 to 107 Ω-cm by increasing the NH 4 OH concentration. • Low NH 4 OH concentration leads to a higher presence of organic compounds in CdS films. • Lower presence of radiative defects in CdS films for the lowest NH 4 OH concentrations. • CdS films deposited by CBD for their use as window layer were obtained. CdS thin films were deposited on commercial glass substrates by CBD technique at constant temperature and deposition time of 90 °C and 50 min, respectively. The reaction was performed by mixing cadmium acetate, ammonium acetate, ammonium hydroxide, thiourea, and deionized water as an aqueous medium. The S/Cd ratio in the solution was kept constant at 4.46 to make sure that the films were as stoichiometric as possible. Optical, electrical, structural properties and the presence of organic compounds in the films were studied modifying the concentration of ammonium hydroxide (complexing agent) in the bath solution. X-ray diffraction patterns show that all films have the cubic phase with a preferential orientation in the plane (1 1 1). An increase of the film's resistivity from 102 to 107 Ω-cm is observed by increasing the ammonium hydroxide concentration in the solution in the narrow interval of 0.18–0.36 M. Transmittance values up to 70% are obtained at the lowest concentrations of this reagent, obtaining from these spectra the highest value of the direct bandgap, 2.37 eV. Results about the presence of organic compounds and their influence on the photoluminescence properties are shown, which have not been reported to date. The main organic compound identified by FTIR is cyanamide, whose concentration is higher at the lowest ammonium hydroxide concentrations. Photoluminescence spectra of the films show green, red and orange bands, located at 2.27 eV, 1.78 eV, and 2.02 eV, respectively. An additional band was observed with low intensity at 2.99 eV associated with the presence of nanoparticles in some films. The films with the lower presence of defects, higher uniformity and best optical, electrical and structural properties for their use as window material in solar cells are those deposited from a bath solution with a 0.24 M concentration of the complexing agent. [ABSTRACT FROM AUTHOR]