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A series of photoreactive complexes of the type Ru(terpy*)(N-N)(L)(2+), where terpy* is 4'-(3,5-ditertiobutylphenyl)-2,2':6',2' '-terpyridine, N-N is the bidentate chelate phen or dmp (phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline), and L is the monodentate ligand dms, MeBN, or MeOBN (dms = dimethyl sulfide, MeBN = 2,6-dimethyl benzonitrile, MeOBN = 2,6-dimethoxybenzonitrile), has been synthesized and fully characterized by proton NMR spectroscopy, electrospray mass spectrometry, and UV-vis spectroscopy. The X-ray structures of four complexes were also obtained. In neat pyridine, the quantum yields for the photosubsitution of L by pyridine were measured and showed dramatic variations depending on the steric interactions between the spectator bidentate ligand and the leaving monodentate ligand L. The use of dmp instead of phen multiplied the photosubstitution efficiency by a factor of 20-50, depending on L. This effect could be qualitatively correlated to the distortions observed in the X-ray structures of the corresponding complexes. The highly distorted structure of Ru(terpy)(dmp)(dms)(PF(6))(2) showed a very high photosubsitution quantum yield phi = 0.36 in neat pyridine. The high photoreactivity of some of the compounds makes them particularly promising as components of future light-driven molecular machines. 相似文献
3.
Collin C. Carbno 《International Journal of Theoretical Physics》1987,26(6):593-606
An alternative method of obtaining the equilibrium configurations of a rotating body consisting of a perfect fluid is outlined. Basically, the method involves recasting the gravitational hydrodynamic equations into a set of partial differential equations of first order in the radial direction such that a center-outward integration can be performed. Specifically, with suitable initial conditions at the origin of anr, grid, a numerical integration is performed outward along a number of selected-rays, with the required derivatives at each step being determined numerically from the values of the functions on the different rays. Applicable to both Newtonian and relativistic formulations, the technique is similar to that often used to obtain equilibrium configurations in spherically symmetric models. 相似文献
4.
The decays of3 S 1 quarkonia into a photon and a scalar or pseudoscalar Higgs particle are examined, taking into account the bound-state dynamics in the framework of a nonrelativistic potential model. We find that for realistic quark potentials the naive calculation [1] overestimates the scalar rate. Numerical results are obtained for the \(\bar bb\) and \(\bar tt\) quark systems. 相似文献
5.
The vibrational spectra of a number of transition-metal complexes containing terminal or bridging nitrido (N3?) and oxo (O2?) ligands are reported. Full assignments of fundamental modes are given for (OsO314N)?, (OsO315N)?, (Os14NX4)?, (Os15NX4)?, (Ru14NX4)?, (Os14NX5)2?, (Os15NX5)2? and (Ru14NX5)2? (X = Cl, Br), and also for the oxo complexes (Mo16OCl4, (Mo18OCl4)?, (Mo16OCl5)2? and (Mo18OCl5)2?. Force constants have been evaluated for the four- and five-coordinate complexes. The significance of the results is discussed in terms of the metalligand bonding involved in these species. 相似文献
6.
Douglas X. West Collin P. Galloway Catherine A. Paulson Roger K. Bunting Lewis K. Pannell 《Transition Metal Chemistry》1989,14(6):420-424
Summary CoII complexes of various stoichiometries have been isolated from reactions of the metal chlorides and bromides withN-2-(4-picolyl)-,N-2-(6-picolyl)- andN-2-(4,6-lutidyl)-N-phenylthioureas. 相似文献
7.
Hartmut Wetzel 《Fresenius' Journal of Analytical Chemistry》1958,164(4):407-408
Zusammenfassung Es werden verschiedene konstruktive Änderungen der Apparatur von Weygand u. Werner für quantitative Hydrierungen beschrieben, die die Rührung, das Einbringen der Substanz und die Sicherheit des Gerätes betreffen. 相似文献
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