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181.
I. B. Krynetskii V. A. Kulbachinskii N. P. Shabanova A. V. Tsikunov R. I. Kovalenko V. V. Rodin S. Yu. Gavrilkin 《Journal of Experimental and Theoretical Physics》2013,116(5):872-875
The temperature dependence of the linear thermal expansion coefficient (TEC) of an InSe single crystal in the (001) plane is measured in the temperature range 7–50 K. A peak in the thermal expansion is detected near T = 10 K, after which the sample shrinks upon heating. The effect of an external magnetic field of up to 6 T, which is parallel to the (001) plane, on the TEC is investigated. The observed partial suppression of the peak and crystal compression by the field indicates the relation of these anomalies to possible electron ordering in InSe layers. 相似文献
182.
S. A. D’yachenko V. F. Kovalenko B. N. Tanygin A. V. Tychko 《Physics of the Solid State》2008,50(1):32-42
The planar Bloch wall is considered in an infinite (001) plate of a cubic crystal with a negative first magnetic anisotropy constant for various values of the ratio between the magnetocrystalline-anisotropy and demagnetization energy densities of the sample. The energy and structure of the Bloch wall are shown to depend on this ratio and on the orientation of a vector equal to the difference between the magnetization vectors of the neighboring domains. 相似文献
183.
184.
Mingze Li Jun Zhou Guojun Zhou Maxim S. Molokeev Jing Zhao Viktoriia Morad Maksym V. Kovalenko Zhiguo Xia 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(51):18843-18848
Very little is known about the realm of solid‐state metal halide compounds comprising two or more halometalate anions. Such compounds would be of great interest if their optical and electronic properties could be rationally designed. Herein, we report a new example of metal halide cluster‐assembled compound (C9NH20)9[Pb3Br11](MnBr4)2, featuring distinctly different anionic polyhedra, namely, a rare lead halide cluster [Pb3Br11]5? and [MnBr4]2?. In accordance with its multinary zero‐dimensional (0D) structure, this compound is found to contain two distinct emission centers, 565 nm and 528 nm, resulting from the formation of self‐trapped excitons and 4T1‐6A1 transition of Mn2+ ions, respectively. Based on the high durability of (C9NH20)9[Pb3Br11](MnBr4)2 upon light and heat, as well as high photoluminescence quantum yield (PLQY) of 49.8 % under 450 nm blue light excitation, white light‐emitting diodes (WLEDs) are fabricated, showcasing its potential in backlight application. 相似文献
185.
Andrienko I. V. Kovalenko E. A. Karmadonova I. E. Plyusnin P. E. Samsonenko D. G. Fedin V. P. 《Russian Journal of Coordination Chemistry》2019,45(6):433-438
Russian Journal of Coordination Chemistry - Supramolecular complexes [Zn(H2O)4(C36H36N24O12)](NO3)2 · 6.5H2O (I), [Zn(H2O)4-(C36H36N24O12)](NO3)2 · 7H2O (II), and... 相似文献
186.
The absorption spectrum of Cs2ZnI4 thin films in the energy range 3–6 eV at temperatures from 90 to 340 K has been investigated. It is established that this compound belongs to direct-gap insulators. Low-frequency exciton excitations are localized in ZnI4 structural elements of the lattice. Phase transitions at 280 K (paraelectric phase ? incommensurate phase), 135 K (incommensurate phase ? monoclinic ferroelastic phase), and 96 K (monoclinic phase ? triclinic ferroelastic phase) have been found from the temperature dependences of the spectral position and halfwidth of the low-frequency exciton band. Additional broadening of the exciton band is observed for ferroelastic phases; it is likely to be due to exciton scattering from strain fluctuations near domain walls. 相似文献
187.
Kovalenko E. A. Maynichev D. A. Masliy A. N. Kuznetsov A. M. 《Russian Chemical Bulletin》2015,64(8):1906-1911
Russian Chemical Bulletin - The l-isoleucine — cucurbit[7]uril system in solution was studied at various concentrations by NMR spectroscopy. The 1H NMR spectra of the L-isoleucine complex... 相似文献
188.
I. B. Krynetskii V. A. Kul’bachinskii M. V. Golubkov G. A. Kalyuzhnaya N. P. Shabanova V. V. Rodin S. Yu. Gabrilkin V. I. Kovalenko 《Journal of Experimental and Theoretical Physics》2014,119(3):542-546
The thermal expansion of a high-quality 2H-NbSe2 single crystal is precisely measured in the basal plane and the temperature range 5.7–50 K. An anomaly of the thermal expansion in the basal plane is detected, and it is found to be caused by a superconducting transition. The change in thermal expansion coefficient α ab is used to calculate the pressure derivative of the critical temperature (dT c /dp ab ) = (19.0 ± 2.0) × 10?9 K/Pa, and this derivative agrees well with the reported data. An additional anomaly, which indicates a phase transition, is also detected in the pretransition range. The nature of the detected phase transition is discussed. 相似文献
189.
Chaikov L. L. Kovalenko K. V. Krivokhizha S. V. Kudryavtseva A. D. Tareeva M. V. Tcherniega N. V. Shevchenko M. A. 《Physics of Wave Phenomena》2019,27(2):87-90
Physics of Wave Phenomena - It is shown by optical methods using light scattering intensity and shift of the stimulated low- frequency Raman scattering line that emulsion particles of the Emulson... 相似文献
190.
Viktoriia Morad Dr. Michael Wörle Dr. Sergii Yakunin Dr. Gabriele Rainò Olga Nazarenko Markus Fischer Dr. Ivan Infante Prof. Dr. Maksym V. Kovalenko 《Angewandte Chemie (International ed. in English)》2018,57(35):11329-11333
The spatial localization of charge carriers to promote the formation of bound excitons and concomitantly enhance radiative recombination has long been a goal for luminescent semiconductors. Zero‐dimensional materials structurally impose carrier localization and result in the formation of localized Frenkel excitons. Now the fully inorganic, perovskite‐derived zero‐dimensional SnII material Cs4SnBr6 is presented that exhibits room‐temperature broad‐band photoluminescence centered at 540 nm with a quantum yield (QY) of 15±5 %. A series of analogous compositions following the general formula Cs4?xAxSn(Br1?yIy)6 (A=Rb, K; x≤1, y≤1) can be prepared. The emission of these materials ranges from 500 nm to 620 nm with the possibility to compositionally tune the Stokes shift and the self‐trapped exciton emission bands. 相似文献