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Yuri A. Berlin Alexander L. Burin Vitalii V. Goldanskii 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1996,37(4):333-339
The “paradox of optical isomers” revealed by Hund in 1927 is re-examined taking into account the interaction of a chiral molecule with phonons of optically inactive solids below the Debye temperature θD. It has been shown, that in the strong coupling limit, where the dephasing rate is much higher than the energy splitting frequency, the interaction can lead to a complete loss of coherence between mirror-antipodal states of the molecule due to the phonon-induced dephasing. This, in turn, suppresses tunnelling oscillations between them, so that transitions, which are reversible in time for an isolated chiral molecule become irreversible for the same molecule placed in a low-temperature matrix. In order to propose a particular mechanism of such stabilization, contributions of a single- and multi-phonon processes in the dephasing rate have been evaluated. It has been established that only the two-phonon scattering provides the sufficiently strong dephasing in low-temperature solids. Such a two-phonon mechanism is responsible for the stabilization of molecular chiral states as long as the temperature of the medium is lower θD, but exceeds a few Kelvin degrees. These findings are discussed in the context of the evolutionary concept known as “the cold prehistory of life”. 相似文献
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A. A. Fagin D. M. Kuzyaev M. A. Burin O. V. Kuznetsova N. M. Khamaletdinova T. I. Kulikova A. F. Shestakov T. I. Lopatina D. L. Vorozhtsov M. N. Bochkarev 《Russian Journal of Coordination Chemistry》2018,44(2):127-131
The thermal decomposition of cluster Nd3I5(S2)(S2N2)(THF)10 (I) at 50–400°C affords a mixture of products among which tetrahydrofuran (THF), sulfur, diiodine, HI, H2S, CS2, S3N6, S3N5, MeI, thiophene, tetrahydrothiophene, diiodobutane, iodobutene, and NdI3 are identified. The treatment of Ln3I5(S2)(S2N2)(THF)10 (Ln = Nd (I), Dy (II)) with phenanthroline (Phen) in THF at room temperature results in the partial substitution of ТНF to form new complexes Ln3I5(S2)(S2N2)(THF)4(Phen)3. The dissolution of compound I in pyridine gives a pyridine (Py) complex Ln3I5(S2)(S2N2)(THF)3(Py)7. The dissolution of compounds I and II in acetonitrile at 20°C is accompanied by the fast rearrangement and fragmentation of the complexes to form LnI3(MeCN)6, [LnI(S2)(MeCN)], and [LnI(S2N2)(MeCN)]. Complex I in THF does not react with white phosphorus, carbon monoxide, fullerene C60, and chromium hexacarbonyl. 相似文献
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We present a numerical study of lasing modes in diffusive random media with local pumping. The reabsorption of emitted light suppresses the feedback from the unpumped part of the sample and effectively reduces the system size. The lasing modes are dramatically different from the quasi modes of the passive system (without gain or absorption). Even if all the quasi modes of a passive diffusive system are extended across the entire sample, the lasing modes are still confined in the pumped volume with an exponential tail outside it. The reduction of effective system volume by absorption broadens the distribution of decay rates of quasi modes and facilitates the occurrence of discrete lasing peaks. 相似文献
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We applied a finite-difference time domain algorithm to the study of field and intensity correlations in random media. Close to the onset of Anderson localization, we observe deviations of the correlation functions, in both shape and magnitude, from those predicted by the diffusion theory. Physical implications of the observed phenomena are discussed. 相似文献
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M. E. Burin A. A. Logunov N. O. Druzhkov G. K. Fukin M. N. Bochkarev 《Russian Chemical Bulletin》2011,60(8):1586-1590
Neodymium diiodide hydride under mild conditions adds at the carbonyl group of benzophenone to give (diphenylmethoxy)(diiodo)neodymium(iii) of the formula I2Nd(OCHPh2)(THF)4. In reactions of NdI2H and DyI2H with N-(2,6-diisopropylphenyl)-9,10-phenanthrenequinonimine, the system of conjugated C=N and C=O groups of the quinone is reduced. The resulting o-aminophenanthrolate complexes are structurally characterized by X-ray diffraction. 相似文献
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Theerakarn Phetnora Roongtum Sooksan Burin Gumjudpai 《General Relativity and Gravitation》2010,42(2):225-240
We describe non-flat standard Friedmann cosmology of canonical scalar field with barotropic fluid in form of non-linear Schrödinger-type (NLS) formulation in which all cosmological dynamical quantities are expressed in term of Schrödinger quantities as similar to those in time-independent quantum mechanics. We assume the expansion to be superfast, i.e. phantom expansion. We report all Schrödinger-analogous quantities to scalar field cosmology. Effective equation of state coefficient is analyzed and illustrated. We show that in a non-flat universe, there is no fixed w eff value for the phantom divide. In a non-flat universe, even w eff > ?1, the expansion can be phantom. Moreover, in open universe, phantom expansion can happen even with w eff > 0. We also report scalar field exact solutions within frameworks of the Friedmann formulation and the NLS formulation in non-flat universe cases. 相似文献
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JETP Letters - The interaction between tunneling system inherent in amorphous solids is established to be responsible for the universal behavior of their kinetics and thermodynamic properties at... 相似文献
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The standard tunneling model describes quite satisfactorily the properties of amorphous solids at temperatures T < 1K in terms of an ensemble of two-level systems including the logarithmic temperature dependence of the dielectric constant. Yet, experiments have shown that at ultralow temperatures T< 5 mK such a temperature behavior breaks down and the dielectric constant becomes temperature independent (plateau effect). In this Letter we suggest an explanation of this behavior exploiting the effect of the nuclear quadrupole interaction on tunneling. We also predict that the application of a sufficiently large magnetic field B> 10T should restore the logarithmic dependence because of the suppression of the nuclear quadrupole interaction. 相似文献