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991.
Aldridge S Kays DL Al-Fawaz A Jones KM Horton PN Hursthouse MB Harrington RW Clegg W 《Chemical communications (Cambridge, England)》2006,(24):2578-2580
The reaction of (eta(5)-C5H5)Fe(CO)2B(C6F5)2 with CO has been shown to proceed via ligand substitution at the metal with accompanying transfer of the boryl fragment (via C-H insertion) to the Cp ring, thereby generating the zwitterion [eta(5)-C5H4B(C6F5)2H]Fe(CO)3 in quantitative yield. 相似文献
992.
All of the copper in the layered oxysulfides Sr2MnO2Cu1.5S2 and Sr2MnO2CU3.5S3 may be extruded as the element and the copper ions replaced quasi-reversibly by lithium ions in reductive topotactic ion exchange reactions; dramatic changes in magnetic properties result. 相似文献
993.
Bowes KF Cole JM Husheer SL Raithby PR Savarese TL Sparkes HA Teat SJ Warren JE 《Chemical communications (Cambridge, England)》2006,(23):2448-2450
The structure of a new metastable geometric isomer of [Ru(NH3)4(H2O)(SO2)][MeC6H4SO3]2 in which the SO2 group is coordinated through a single oxygen in an eta1-OSO bonding mode has been determined at 13 K; the new isomer was obtained as a 36% component of the structure within a single crystal upon irradiation using a tungsten lamp. 相似文献
994.
A macrocyclic amidourea shows anion dependent binding modes with a variety of different putative anionic guests. 相似文献
995.
The linear and nonlinear optical responses of the three aromatic amino acids tryptophan, tyrosine, and phenylalanine have been investigated by time-dependent density functional theory. The effect of the peptidic chain on the polarizabilities and the first hyperpolarizabilities is addressed by substituting different groups to the chromophores indole, phenol, and benzene. The optimized structures are in very good agreement with the experimental results. Furthermore, the calculated polarizabilities are found to match well with the empirical results, showing the evolution obtained as the chain is lengthened. A systematic and constant increase of the polarizability is found, for the three chromophores, for the various chain lengths. The first hyperpolarizability is also noticeably modified by the chains, but the evolution of this quantity is found to be more dependent on the system considered. Finally, it is suggested that each of the three aromatic amino acids has a significant contribution to the nonlinear response of proteins. 相似文献
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