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101.
The effect of electromagnetic retardation on the spectrum of edge plasmons in a semi-infinite two-dimensional electron system is considered. The problem is reduced to complicated integral equations for the potentials, which are solved upon a major simplification of the kernel. The spatial distribution of the potentials, charges, and currents is analyzed. It is shown that edge plasmon polaritons in the high-conductivity two-dimensional system are characterized by a high Q factor at all frequencies, including those lower than the reciprocal electron relaxation time τ-1. 相似文献
102.
103.
E. A. Il'inchik T. M. Polyanskaya M. K. Drozdova K. G. Myakishev V. N. Ikorskii V. V. Volkov 《Russian Journal of General Chemistry》2005,75(10):1545-1552
[Tris(1,10-phenanthroline)manganese](2+) 1,2;1′,2′-trans-bis[nonahydro-closo-decaborate](2?) bis(dimethylformamide) containing the complex anion [MnPhen3]2+ with the paramagnetic central Mn atom and the [B20H18]2? anion formed by fusion of two closo clusters B10H9 was synthesized and characterized by single crystal X-ray diffraction and by IR, X-ray photoelectron, and Raman spectroscopy. 相似文献
104.
N. K. Gusarova P. A. Volkov N. I. Ivanova N. A. Chernysheva S. V. Yas’ko A. I. Albanov B. A. Trofimov 《Russian Journal of General Chemistry》2010,80(8):1602-1608
Under the conditions of free-radical initiation (AIBN, UV irradiation), divinyl selenide regioselectively reacts with secondary
phosphine sulfides and phosphine selenides to afford, depending on the ratio of the reagents, mono- or diadducts mainly of
the anti-Markownikoff structure. The conditions which allow obtaining the diadducts in up to 97% yield are found. By the example
of 2-{[2-(diphenethylphosphoroselenoyl) ethyl]selanyl}ethyl(diphenethyl)phosphine selenide the diadducts were shown to react
with aqueous hydrogen peroxide at 53–56°C to give vinyl(diphenethyl)phosphine oxide in 76% yield. 相似文献
105.
Paarmann A Lima M Chelli R Volkov VV Righini R Miller RJ 《Physical chemistry chemical physics : PCCP》2011,13(23):11351-11358
The linear and two-dimensional infrared (2DIR) responses of the amide I vibrational mode in liquid formamide are investigated experimentally and theoretically using molecular dynamics simulations. The recent method based on the numerical integration of the Schr?dinger equation is employed to calculate the 2DIR spectra. Special attention is devoted to the interplay of the structural dynamics and the excitonic nature of the amide I modes in determining the optical response of the studied system. In particular, combining experimental data, simulated spectra and analysis of the simulated atomic trajectory in terms of a transition dipole coupling model, we provide a convincing explanation of the peculiar features of the 2DIR spectra, which show a substantial increase of the antidiagonal bandwidth with increasing frequency. We point out that, at variance with liquid water, the 2DIR spectral profile of formamide is determined more by the excitonic nature of the vibrational states than by the fast structural dynamics responsible for the frequency fluctuations. 相似文献
106.
X-Ray and X-ray Photoelectron Spectroscopy Studies of the Electronic Structure of Borane Derivatives
V. D. Yumatov E. A. Il'inchik L. N. Mazalov O. V. Volkov V. V. Volkov 《Journal of Structural Chemistry》2001,42(2):281-295
This paper reviews the results of electronic structure studies of a number of typical members of borane series by X-ray and X-ray photoelectron spectroscopy using quantum chemical calculations. Fragment analysis of the molecular orbital structure is given. The nature of chemical interaction in boron cluster compounds is studied on models: simple molecules NH3, BH3, and BF3 and their adducts NH3BH3 and NH3BF3. The electronic structure of B10H12L2 type compounds with Lewis bases L = NH3, (CH3)2S, (C6H5)3P is analyzed. The complexes are considered in terms of the concept of donor–acceptor interactions between the fragments. The donor–acceptor bond has contributions from both occupied and vacant acceptor orbitals. X-ray photoelectron data on the charged states of atoms in the compounds are overviewed. Electron distribution in complex compounds with transition metals [(1,2-B9C2H11)2M]–, M = FeIII, CoIII, NiIII, and NiIV and chain type polycobaltocarborane anions {[(3)-1,2-B9C2H11]2Co
n
[(3,6)-1,2-B8C2H10]n-1}
n–
, n = 2-7, is considered. 相似文献
107.
Recent measurements of the conductivity of nanoperforated graphene are interpreted in terms of edges states existing near the edge of each nanohole. The perimetric quantization of edge states should result in the formation of a quasi-equidistant ladder of quasistationary energy levels. Dirac fermions filling this ladder rotate about each nanohole in the direction determined by the valley index. It is shown that the irradiation of this system by circularly polarized terahertz radiation leads to a resonance in absorption in one of the valleys. The magnitude of absorption at the resonance frequency can be controlled by means of gate voltage. 相似文献
108.
A. M. Tikhonov V. E. Asadchikov Yu. O. Volkov B. S. Roshchin I. S. Monakhov I. S. Smirnov 《JETP Letters》2016,104(12):873-879
The ordering of a multilayer consisting of DSPC bilayers on a silica sol substrate is studied within the modelindependent approach to the reconstruction of profiles of the electron density from X-ray reflectometry data. It is found that the electroporation of bilayers in the field of anion silica nanoparticles significantly accelerates the process of their saturation with Na+ and H2O, which explains both a relatively small time of formation of the structure of the multilayer of 1–7×105 s and ~13% excess of the electron density in it. 相似文献
109.
A. Shumelyuk A. Volkov S. Odoulov G. Cook D. R. Evans 《Applied physics. B, Lasers and optics》2010,100(1):101-108
Coupling of two counterpropagating coherent light waves in tin hypothiodiphosphate (Sn2P2S6, SPS) is usually strongly inhibited because of severe space charge limitations. Analysis of two-beam coupling gain is performed for different orientations of the grating vector in this monoclinic crystal that takes into account the anisotropy of dielectric permittivity. Gain enhancements are predicted and demonstrated experimentally for several nontraditional orientations of counterpropagating waves. 相似文献
110.
Kuznetsov V. V. Podlovchenko B. I. Frolov K. V. Volkov M. A. Khanin D. A. 《Russian Journal of Electrochemistry》2022,58(10):896-906
Russian Journal of Electrochemistry - The composite materials involving platinum nanoparticles on the surface of carbides of Mo, Zr, and Nb are synthesized by the currentless redox reaction between... 相似文献