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991.
The acetone molecule is investigated in its ground state and valence 1,3n-π*, 1,3π-π*, and 1,3σ-π* excited states and Rydberg 1,3n-3s, 1,3π-3?, 1,3n-3py and 1,3π-3py states using the CASSCF, CASPT2, and CCSD(T) methods. Equilibrium geometries of excited states are obtained and their changes with respect to the ground state are discussed. For most excited states the C2v symmetry of the ground state is lowered to the Cs symmetry. A series of valence vertical and adiabatic excitation energies is presented along with excitation energies for Rydberg states. The main body of the paper contains Finite-Field Perturbation Theory (FFPT) calculations of electric properties of the vertically as well as geometry relaxed excited states. Dipole moments of valence excited states decrease significantly upon excitation, being about one half of the ground state dipole moment. Polarizabilities usually change upon excitation much less (increase by about 30%) but hyperpolarizabilities are enhanced up to one or two orders of magnitude. The orientation of the dipole moment is reversed in some vertically excited Rydberg states. Properties of the ground and excited states are discussed considering alterations of the electronic structure and shifts in the geometry. 相似文献
992.
993.
Ana Amić Zoran Marković Jasmina M. Dimitrić Marković Dejan Milenković Bono Lučić 《Molecular physics》2013,111(2):207-217
ABSTRACTParticipation of guaiacyl moiety of 3,5-dihydroxy-4-methoxybenzyl alcohol (DHMBA) in inactivation of free radicals was investigated using the DFT method. The thermodynamics of triple (3H+/3e?) free radical scavenging mechanisms was investigated. The Gibbs free energies of reactions of inactivation of selected 10 free radicals indicate DHMBA as a potent scavenger. Obtained results allow us to suggest that the contribution of guaiacyl moiety to antioxidant activity of phenolic compounds should be taken into account, what has been scarcely considered until now. 相似文献
994.
G. Račiukaitis S. Grubinskas P. Gečys M. Gedvilas 《Applied Physics A: Materials Science & Processing》2013,110(1):93-98
Selectiveness of the laser processing is the top-most important for applications of the processing technology in thin-film electronics, including photovoltaics. Coupling of laser energy in multilayered thin-film structures, depending on photo-physical properties of the layers and laser wavelength was investigated experimentally and theoretically. Energy coupling within thin films highly depends on the film structure. The finite element and two-temperature models were applied to simulate the energy and temperature distributions inside the stack of different layers of a thin-film solar cell during a picosecond laser irradiation. Reaction of the films to the laser irradiation was conditioned by optical properties of the layers at the wavelength of laser radiation. Simulation results are consistent with the experimental data achieved in laser scribing of copper-indium-gallium diselenide (CIGS) solar cells on a flexible polymer substrate using picosecond-pulsed lasers. Selection of the right laser wavelength (1064 nm or 1572 nm) enabled keeping the energy coupling in a well-defined volume at the interlayer interface. High absorption at inner interface of the layers triggered localized temperature increase. Transient stress caused by the rapid temperature rise facilitating peeling of the films rather than evaporation. Ultra-short pulses ensured high energy input rate into absorbing material permitting peeling of the layers with no influence on the remaining material. 相似文献
995.
996.
The objective of this research in the queueing theory is the law of the iterated logarithm (LIL) under the conditions of heavy traffic in multiphase queueing systems (MQS). In this paper, the LIL is proved for the extreme values of some important probabilistic characteristics of the MQS, namely, maxima and minima of the summary waiting time of a customer, and maxima and minima of the waiting time of a customer. 相似文献
997.
A. L. Erzinkyan V. P. Parfenova S. I. Reyman G. M. Gurevich S. V. Topalov M. Trhlík M. Finger V. N. Pavlov M. Slunečko 《Hyperfine Interactions》1993,78(1-4):491-495
An57Fe Mössbauer study and60Co and54Mn nuclear orientation (NO) studies of the Au86Fe14 alloy have been performed. A transition to the spin glass state was observed below approximately 50 K. NO of the60Co impurity showed absence of the polarization of the60Co nuclei. For54Mn impurities the dependence of the Mn effective magnetic field on external field andtemperature was found. 相似文献
998.
R. Marek M. Potáček J. Marek A. De Groot R. Dommisse 《Monatshefte für Chemie / Chemical Monthly》1995,126(10):1151-1159
Summary The preparation of some new 2,2-dimethylpenta-3,4-dienal derivatives starting byClaisen-Cope rearrangement of the pyrolytic product of the corresponding acetales and followed by condensation reactions is described. The synthesis of homoallenylketone5 from homoallenylaldehyde3 byGrignard reaction and followed by the oxidation of the formed alcohol using potassium chlorochromate (KCC) is reported. All new compounds are characterized by IR, MS,1H, and13C NMR spectroscopy. The full assignment of the NMR signals is based on HETCOR and FLOCK pulse sequences. The molecular and crystal structure of 2,2-dimethylhexa-3,4-dienal 2,4-dinitrophenylhydrazone is presented.Dedicated to ProfessorFritz Sauter on the occasion of his 65th birthday 相似文献
999.
V. Kazakevičius 《Lithuanian Mathematical Journal》1993,33(4):330-336
Vilnius University, Naugarduko str. 24, 2006 Vilnius, Lithuania. Translated from Lietuvos Matematikos Rinkinys, Vol. 33, No. 4, pp. 424–434, October–December, 1993. 相似文献
1000.
A discrete limit theorem for the Lerch zeta-function with an integer parameter in the space of meromorphic functions is proved. 相似文献