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1.
The fluorescence spectrum of crystals grown from newly synthesized 4-(dimethylamino)benzonitrile (DMABN), measured from 25 down to −112 °C, consists of a single emission band originating from a locally excited (LE) state. The fluorescence decay of the DMABN crystals is single exponential at all temperatures investigated. These results show that intramolecular charge transfer (ICT) does not occur in crystalline DMABN. The additional red-shifted emission bands and multiexponential fluorescence decays previously reported for DMABN crystals are attributed to a minor amount of the impurity 4-(dimethylamino)benzaldehyde, the synthetic precursor of commercial DMABN. 相似文献
2.
With the purpose of comparing expectation dipole moment values mu with finite-field obtained dipole moments mu(FF), we recalculated by the finite-field method previously reported mu values of 38 excited states of FeC. In most of the cases mu(FF) is significantly larger than mu. 相似文献
3.
Using preilluminating flashes at 2°C prior to continuous excitation of isolated chloroplasts at -80°C, a period-four oscillation with maxima at the 0th, 4th and 8th flashes was observed in the amplitude of the thermoluminescence band Zv . Inactivation of the water-splitting system by hydroxylamine- or Tris-treatments greatly diminished the Zv band. On the other hand, its amplitude was not considerably affected by the addition of inhibitory concentration of DCMU. On the basis of the results, the possible origin of the Zv band is discussed. 相似文献
4.
D. Krupka 《Czechoslovak Journal of Physics》1979,29(3):300-303
The problem of determining all possibleG-invariant interaction Lagrangians for a given system of physical fields and their derivatives, whereG is a Lie subgroup of the general linear groupGL
n
(R), is discussed, and a method for a complete solution of this problem by means of certain jet structures is outlined.Talk given at the Symposium on Mathematical Methods in the Theory of Elementary Particles, Liblice castle, Czechoslovakia, June 18–23, 1978. 相似文献
5.
The second-order generally invariant Lagrangians for the metric fields on anyn-dimensional manifold are studied as certain special coordinate functions on a space of jets. The number of independent Lagrangians of this type is determined. The dimensionsn=3 andn=4 are examined in detail with the help of a computer. 相似文献
6.
Dr. Antoine Leliège M. Sc. Jérémie Grolleau M. Sc. Magali Allain Dr. Philippe Blanchard Dr. Dora Demeter Dr. Théodulf Rousseau Dr. Jean Roncali 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(30):9948-9960
Donor–acceptor (D–π–A) systems that combine triarylamine donor blocks and dicyanovinyl (DCV) acceptor groups have been synthesized. Starting from the triphenylamine (TPA)? thiophene? DCV compound ( 1 ) as a reference system, various synthetic approaches have been developed for controlling the light‐harvesting properties and energy levels of the frontier orbitals in this molecule. Thus, the introduction of methoxy groups onto TPA, the replacement of one phenyl ring of TPA by a thiophene ring, or the extension of the π‐conjugating spacer group lead to the modulation of the HOMO level. On the other hand, the fusion of the DCV group onto the vicinal thiophene ring by an ortho‐phenylene bridge allows for a specific fine‐tuning of the LUMO level. The electronic properties of the molecules were analyzed by using UV/Vis spectroscopy and cyclic voltammetry and the compounds were evaluated as donor materials in basic bilayer planar heterojunction solar cells by using C60 as acceptor material. The relationships between the electronic properties of the donors and the performance of the corresponding photovoltaic devices are discussed. Bilayer planar heterojunction solar cells that used reference compound 1 and C70 afforded power‐conversion efficiencies of up to 3.7 %. 相似文献
7.
Demeter Krupka 《Reports on Mathematical Physics》1974,5(3):355-360
The notion of generalized invariant transformations of variational problems in Lagrangian formulation is discussed in the framework of the variational theory in fibred manifolds. Necessary and sufficient conditions for generators of one-parameter groups of such transformations are derived, completing thus some previous results of A. Trautman on the theory of transformations. 相似文献
8.
9.
V. Tsurkan St. Plogmann M. Demeter D. Hartmann M. Neumann 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,15(3):401-403
X-ray photoelectron spectroscopy was used to investigate ACr2S4 (, Zn, Mn, Fe, Fe:Cu) and BCr2Se4 (, Cu, Hg, Hg:Cu) single crystals. Well defined splitting of the Cr 2p core level has been found. The local magnetic moments of the Cr ions are responsible for the observed effect.
Received 2 November 1999 相似文献
10.