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21.
We have determined the various parameters of the electric field gradient (EFG) for different Fe-oxygen configurations. This was achieved by analyses of a variety of spectra using a procedure which allows fitting of all spectra of oriented 1-2-3 compounds obtained at different tilt angles β simultaneously, taking into account the degree of texture. The use of a point charge model is invalidated because of the high degree of estimated covalence. The Mössbauer parameters are rationalized. The absence of any observed anisotropy of the mean square displacement of the dopant at the Cu(1) site is rather intriguing. 相似文献
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Vladimir B. Arion Alexey A. Nazarov Christian G. Hartinger Gerald Giester Bernhard K. Keppler 《应用有机金属化学》2003,17(9):723-724
For the unsymmetrical title compound, 1‐bromo‐1′‐[(2S)‐N‐(1‐hydroxy‐3‐methylbutane‐2‐yl)]‐ferroceneamide, two independent molecules were found in the asymmetric unit. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Dimitri Markushevich Vladimir B. Matveev Armando Treibich 《Letters in Mathematical Physics》2006,76(2-3):109-109
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Marijana ?aković Zora Popović 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m507-m509
In the title compound, [Ni(N3)2(C6H6N2O)2], the NiII atom lies on an inversion centre. The distorted octahedral nickel(II) coordination environment contains two planar trans-related N,O-chelating picolinamide ligands in one plane and two monodentate azide ligands perpendicular to this plane. Molecules are linked into a three-dimensional framework by N—H...N hydrogen bonds. 相似文献
30.
Vladimir V. Bazhanov Sergei L. Lukyanov Alexander B. Zamolodchikov 《Communications in Mathematical Physics》1997,190(2):247-278
This paper is a direct continuation of [1] where we began the study of the integrable structures in Conformal Field Theory.
We show here how to construct the operators ${\bf Q}_{\pm}(\lambda)$ which act in the highest weight Virasoro module and commute
for different values of the parameter λ. These operators appear to be the CFT analogs of the Q - matrix of Baxter [2], in particular they satisfy Baxter's famous T- Q equation. We also show that under natural assumptions about analytic properties of the operators as the functions of λ the Baxter's relation allows one to derive the nonlinear integral equations of Destri-de Vega (DDV)
[3] for the eigenvalues of the Q-operators. We then use the DDV equation to obtain the asymptotic expansions of the Q - operators at large λ; it is remarkable that unlike the expansions
of the T operators of [1], the asymptotic series for Q(λ) contains the “dual” nonlocal Integrals of Motion along with the local ones. We also discuss an intriguing relation between
the vacuum eigenvalues of the Q - operators and the stationary transport properties in the boundary sine-Gordon model. On this basis we propose a number
of new exact results about finite voltage charge transport through the point contact in the quantum Hall system.
Received: 2 December 1996 / Accepted: 11 March 1997 相似文献