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91.
The transition energies, the oscillator strengths, and the A/D values of porphin, protoporphyrin, and porphyrin a were calculated within the framework of the Pariser -Parr-Pople approximation. The calculated values are in reasonable agreement with the experimental data obtained from the absorption and magnetic circular dichroism spectra of metal porphin, low-spin ferrous protoheme, and low-spin ferrous heme a. The magnetic circular dichroism of the Q and Soret bands in the heme a and the protoheme was analysed in terms of an “apparent” A term which originates from the magnetic mixing between the components of the nearly degenerate excited state. 相似文献
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94.
We study Langevin dynamics describing nonequilibirum steady states. Employing the phenomenological framework of steady-state thermodynamics constructed by Oono and Paniconi [Prog. Theor. Phys. Suppl. 130, 29 (1998)], we find that the extended form of the second law which they proposed holds for transitions between steady states and that the Shannon entropy difference is related to the excess heat produced in an infinitely slow operation. A generalized version of the Jarzynski work relation plays an important role in our theory. 相似文献
95.
Mikami K Yusa Y Hatano M Wakabayashi K Aikawa K 《Chemical communications (Cambridge, England)》2004,(1):98-99
A cationic rhodium(I) complex having a skewphos ligand is shown to be a highly enantioselective catalyst for asymmetric carbocyclization of 1,6-enynes with tri-substituted olefins to control quaternary stereogenic centers of spiro-rings. 相似文献
96.
97.
Kirihara M Okubo K Uchiyama T Kato Y Ochiai Y Matsushita S Hatano A Kanamori K 《Chemical & pharmaceutical bulletin》2004,52(5):625-627
Thiols were converted into disulfide by the aerobic oxidation catalyzed by trichlorooxyvanadium in the presence of molecular sieves 3A. 相似文献
98.
Hatano T 《Physical review letters》2004,93(8):085501
Quantitative behaviors of shock-induced dislocation nucleation are investigated by means of molecular dynamics simulations on fcc Lennard-Jones solids: a model argon. In perfect crystals, it is found that the Hugoniot elastic limit (HEL) is a linearly decreasing function of temperature: from near-zero to melting temperatures. In a defective crystal with a void, dislocations are found to nucleate on the void surface. Also, HEL drastically decreases to 15% of the perfect crystal when the void radius is 3.4 nanometers. The decrease of HEL becomes larger as the void radius increases, but HEL becomes insensitive to temperature. 相似文献
99.
We employ a new laterally coupled, vertical double dot with a tunable tunnel-coupling gate in a parallel configuration to study the electron spin and orbital dependence of quantum mechanical tunnel coupling on the size of the honeycomb vertices in the small electron numbers regime. We find a transition from the weak coupling regime, where fluctuations in tunnel coupling due to varying electron configuration dominate the anticrossings, to a regime where the two dots coalesce. We apply a magnetic field to ascertain the orbital angular momenta of the Fermi surface eigenstates, which correlate with anticrossing size, and we identify spin pairs with congruent behavior. 相似文献
100.
Eri Hatano Prof. Dr. Masakazu Morimoto Dr. Kengo Hyodo Dr. Nobuhiro Yasuda Prof. Dr. Satoshi Yokojima Dr. Shinichiro Nakamura Prof. Dr. Kingo Uchida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12680-12683
Crystals of a diarylethene with a perfluorocyclohexene ring exhibit a remarkable photosalient effect upon UV light irradiation that is attributed to the structural changes that occur when going from open‐ to closed‐ring isomers in the crystalline state, together with the existence of two conformers with different photoconversions compared with those of a perfluorocyclopentene derivative. Our current results give a design principle for molecular structures so as to achieve the photosalient effect for photochromic crystals. 相似文献