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991.
Vitaly E. Matulis Ekaterina G. Ragoyja Oleg A. Ivashkevich 《International journal of quantum chemistry》2020,120(9):e26159
Boron-dipyrromethene dyes (BODIPY) are of great interest nowadays mostly due to their valuable optical properties. Nevertheless, no systematic research of the optical property dependence on the structure of dyes has been performed yet. In this work, analysis of the available quantum-chemical methods for BODIPY optical property calculations has been carried out. The accuracy of eight DFT functionals has been studied. The solvation effects upon excitation have been considered within two schemes. The methods that predict the absorption and emission spectra of BODIPY derivatives with high accuracy have been proposed. Using the suggested methods, the influence of nature of substituents and their position in the BODIPY core on the optical spectra of the dyes has been studied. A complex pattern of red- and blue-shifts in optical spectra in dependence of nature and position of substituents has been revealed. The results of this work provide the way for efficient design of BODIPY derivatives with desired optical properties. 相似文献
992.
Marisa C. Oliveira Renan A. P. Ribeiro Elson Longo Mauricio R. D. Bomio Sergio R. de Lázaro 《International journal of quantum chemistry》2020,120(22):e26368
The structural, electronic, and vibrational properties of two leading representatives of the Zn-based spinel oxides class, normal ZnX2O4 (X = Al, Ga, In) and inverse Zn2MO4 (M = Si, Ge, Sn) crystals, were investigated. In particular, density functional theory (DFT) was combined with different exchange-correlation functionals: B3LYP, HSE06, PBE0, and PBESol. Our calculations showed good agreement with the available experimental data, showing a mean percentage error close to 3% for structural parameters. For the electronic structure, the obtained HSE06 band-gap values overcome previous theoretical results, exhibiting a mean percentage error smaller than 10.0%. In particular, the vibrational properties identify the significant differences between normal and inverse spinel configurations, offering compelling evidence of a structure-property relationship for the investigated materials. Therefore, the combined results confirm that the range-separated HSE06 hybrid functional performs the best in spinel oxides. Despite some points that cannot be directly compared to experimental results, we expect that future experimental work can confirm our predictions, thus opening a new avenue for understanding the structural, electronic, and vibrational properties in spinel oxides. 相似文献
993.
994.
995.
Kislitsin A. A. Drachuk A. O. Molokitina N. S. Podenko L. S. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):405-411
Russian Journal of Physical Chemistry A - The kinetics of methane hydrate formation in “dry water” is studied using a diffusion model (the well-known modified shrinking core model). An... 相似文献
996.
997.
Mathematical Notes - For the monotone symmetric threshold Boolean functions $$ f^n_2(\widetilde x\mspace{2mu})=\bigvee_{1\le i 相似文献
998.
Doklady Mathematics - In this paper we extend Y. Eliashberg’s theorem on the maps with fold type singularities to arbitrary Thom-Boardman singularities. Namely, we state a necessary and... 相似文献
999.
Doklady Mathematics - This paper shows the integrability of certain classes of odd-order dynamical systems that are homogeneous with respect to some of the variables and in which a system on the... 相似文献
1000.
N. Stallkamp S. Ringleb B. Arndt M. Kiffer S. Kumar T. Morgenroth G.G. Paulus W. Quint Th. Stöhlker M. Vogel 《X射线光谱测定》2020,49(1):188-191
Detailed investigations of laser–ion interactions require well-defined ion targets and detection techniques for high-sensitivity measurements of reaction educts and products. To this end, we have designed and built the High-Intensity Laser-Ion Trap Experiment Penning trap setup, which features various ion-target preparation techniques including selection, cooling, compression, and positioning as well as destructive and non-destructive measurement techniques to determine the number of stored ions for all charge states individually and simultaneously. We have recently performed first commissioning experiments of ion deceleration and dynamic ion capture with highly charged ion bunches from an electron beam ion source. We have characterized our single-pass non-destructive ion counter in detail and were able to determine the ion velocity as well as the number of ions from the signals acquired. 相似文献