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Saulius Mickevičius Darius Germanas Ramutis K. Kalinauskas 《Central European Journal of Physics》2013,11(5):568-574
A new procedure for large-scale calculations of the coefficients of fractional parentage (CFP) for many-particle systems is presented. The approach is based on a simple enumeration scheme for antisymmetric N particle states, and we suggest an efficient method for constructing the eigenvectors of two-particle transposition operator $P_{N_1 ,N}$ in a subspace where N 1 and N 2 = N ? N 1 nucleons basis states are already antisymmetrized. The main result of this paper is that according to permutation operators $P_{N_1 ,N}$ eigenvalues we can distinguish totally asymmetrical N particle states from the other states with lower degree of asymmetry. 相似文献
15.
Dev Raj Chopra Justin Seth Pearson Darius Durant Ritesh Bhakta Anil R. Chourasia 《Surface and interface analysis : SIA》2019,51(2):246-253
The Ti/CuO interface has been studied by the techniques of X-ray photoelectron spectroscopy and atomic force microscopy. Thin films of titanium were deposited on a CuO substrate at room temperature by the e-beam technique. The photoelectron spectra of titanium and copper were found to exhibit significant chemical interaction at the interface. The titanium overlayer was observed to get oxidized to TiO2, while the CuO was observed to get reduced to elemental copper. This chemical interaction was observed to occur until a thickness of 7 nm of the titanium overlayer. For thicknesses greater than this value, the presence of unreacted titanium in the sample was detected. Barrier characteristics at the Ti/CuO interface were also carried out for substrate temperatures of 300°C, 400°C, 500°C, and 600°C as a function of the titanium overlayer thickness. A linear trend in the barrier thickness of the overlayer was observed between 400°C and 600°C substrate temperatures. The atomic force microscopy micrographs of the unannealed samples depicted layer-by-layer growth of elemental titanium on copper. At the Ti/CuO interface in such samples, the micrographs exhibited island formation of TiO2 corresponding to the Volmer-Weber growth model. This formation has been interpreted as the relaxation in the strain energy. The percentage coverage of the underlying substrate by the TiO2 islands showed a linear trend for the thicknesses of the titanium overlayer investigated. The average size of these islands also showed a linear trend as a function of the thickness of the overlayer. 相似文献
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Variability of UV irradiance in Europe 总被引:1,自引:1,他引:0
Seckmeyer G Pissulla D Glandorf M Henriques D Johnsen B Webb A Siani AM Bais A Kjeldstad B Brogniez C Lenoble J Gardiner B Kirsch P Koskela T Kaurola J Uhlmann B Slaper H den Outer P Janouch M Werle P Gröbner J Mayer B de la Casiniere A Simic S Carvalho F 《Photochemistry and photobiology》2008,84(1):172-179
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The nonlinear optical signal generated in phenol by three femtosecond pulses with wavevectors k1, k2, and k3 in the phase-matching direction k1 + k2 - k3 is simulated. This two-dimensional coherent spectroscopy (2DCS) signal has a rich pattern containing information on double-excitation states. The signal vanishes for uncorrelated electrons due to interference among quantum pathways and, thus, provides direct signatures of correlated many-electron wavefunctions. This is illustrated by the very different 2DCS signals predicted by two levels of electronic structure calculations: state-averaged complete active space self-consistent field (SA-CASSCF) and multistate multiconfigurational second-order perturbation theory (MS-CASPT2). 相似文献
18.
Ma?vydas Mackevi?ius Feliksas Ivanauskas Aivaras Kareiva Darius Jasaitis 《Journal of mathematical chemistry》2012,50(8):2291-2302
Recently, we presented a method for estimation of the diffusion and reaction rates of synthesis at high temperatures using limited information, such as synthesis time and dimensions of reactants, from real laboratory experiments (Mackevi?ius et?al. in Central Eur J Chem 10(2):380–385, 2012). There, we restricted ourselves to the one- and two-dimensional models. Having both adapted our computing program to the three-dimensional case and significantly speeded it up, now we are able present the results in the three-dimensional model. Solving an inverse modeling problem, we obtain explicit formulas for the diffusion coefficient and reaction rate as functions of temperature. We calculate the activation energies and other parameters, thus obtaining conditions for occurrence of synthesis. In addition, using the results of the three-dimensional model, we find the optimal temperature for energy consumption in the YAG synthesis. 相似文献
19.
Abramavicius D Nemeth A Milota F Sperling J Mukamel S Kauffmann HF 《Physical review letters》2012,108(6):067401
The two-exciton manifold of a double-wall cylindrical molecular aggregate is studied using a coherent third order optical technique. Experiments reveal the anharmonic character of the exciton bands. Atomistic simulations of the exciton-exciton scattering show that the excitons can be treated as weakly coupled hard-core bosons. The weak coupling stems from the extended exciton delocalization made possible by the nanotube geometry. 相似文献