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91.
The synthesis and luminescence properties are reported for 20 different chelates composed of 2,2′:6′,2″-terpyridine as the energy-absorbing and donating group, EuIIIand TbIII as the emitting ions, methylenenitrilo(acetic acids) as the stabel chelate-forming moieties, and isothiocyanato or(4,6-dichloro-1,3,5-triazin-2-yl)amino groups as the activated moieties for coupling to biomolecules.  相似文献   
92.
Reactions during the atomic layer deposition (ALD) process of ZrO(2) from Cp(2)Zr(CH(3))(2) and deuterated water as precursors were studied with a quadrupole mass spectrometer (QMS) at 210-440 degrees C. The detected reaction byproducts were CpD (m/z = 67) and CH(3)D (m/z = 17). Almost all (90%) of the CH(3) ligands were released during the Cp(2)Zr(CH(3))(2) precursor pulse because of exchange reactions with the OD-terminated surface, and the rest, during the D(2)O pulse. About 40% of the CpD was released during the metal precursor pulse, and 60%, during the D(2)O pulse. ALD-type self-limiting growth was confirmed from 210 to 400 degrees C. However, below 300 degrees C the growth rate was low. Precursor decomposition affected the film growth mechanism at temperatures exceeding 400 degrees C.  相似文献   
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The theoretical data for the half-lantern complexes [{Pt( )(μ- )}2] [ 1 – 3 ; is cyclometalated 2-Ph-benzothiazole; is 2-SH-pyridine ( 1 ), 2-SH-benzoxazole ( 2 ), 2-SH-tetrafluorobenzothiazole ( 3 )] indicate that the Pt ⋅⋅⋅ Pt orbital interaction increases the nucleophilicity of the outer d orbitals to provide assembly with electrophilic species. Complexes 1 – 3 were co-crystallized with bifunctional halogen bonding (XB) donors to give adducts ( 1 – 3 )2 ⋅ (1,4-diiodotetrafluorobenzene) and infinite polymeric [ 1⋅ 1,1′-diiodoperfluorodiphenyl]n. X-ray crystallography revealed that the supramolecular assembly is achieved through (Aryl)I ⋅⋅⋅ d [PtII] XBs between iodine σ-holes and lone pairs of the positively charged (PtII)2 centers acting as nucleophilic sites. The polymer includes a curved linear chain ⋅⋅⋅ Pt2 ⋅⋅⋅ I(areneF)I ⋅⋅⋅ Pt2 ⋅⋅⋅ involving XB between iodine atoms of the perfluoroarene linkers and (PtII)2 moieties. The 195Pt NMR, UV/Vis, and CV studies indicate that XB is preserved in CH(D)2Cl2 solutions.  相似文献   
95.
A new series of homoleptic alkynyl complexes, [{Au2Cu2(C2R)4}n] (R=C3H7O ( 1 ), C6H11O ( 2 ), C9H19O ( 3 ), C13H11O ( 4 )), were obtained from Au(SC4H8)Cl, Cu(NCMe)4PF6, and the corresponding alkyne in the presence of a base (NEt3). Complexes 1 – 4 aggregate upon crystallization into polymeric chains through extensive metallophilic interactions. The cluster that contains fluorenolyl functionalities, C13H9O ( 5 ), crystallizes in its molecular form as a disolvate, [Au2Cu2(C2C13H9O)4] ? 2 THF. The substitution of weakly bound THF molecules with pyridine molecules leads to the complex [Au2Cu2(C2C13H9O)4] ? 2 py ( 6 ), thus giving two polymorphs in the solid state. Such structural diversity is established through metal‐chain and hydrogen‐bond formation, which depends on the stereochemical characteristics of the organic ligands. More interestingly, this solid‐state structural arrangement affords good emission properties, such as intensity and spectroscopic profile, which are otherwise very weakly emissive in solution. Metallophilic aggregation of the {Au2Cu2} cluster units, as observed in the crystals, results in dramatic enhancement of the room‐temperature phosphorescence, thereby reaching a maximum quantum efficiency of 95 % ( 4 ). A theoretical approach further indicates a synergistic effect of the array of the metal chain upon aggregation, which greatly enhances the spin‐orbit coupling and, hence, the phosphorescence, thereby opening up a new direction in the field of aggregate‐enhanced emission.  相似文献   
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A general organometallic route has been developed to synthesize Co(x)Ni(1-x) and Co(x)Fe(1-x) alloy nanoparticles with a fully tunable composition and a size of 4-10?nm with high yield. In contrast to previously reported synthesis methods using dicobalt octacarbonyl (Co(2)(CO)(8)), here the cobalt-cobalt bond in the carbonyl complex is first broken with anhydrous acetone. The acetonated compound, in the presence of iron carbonyl or nickel acetylacetonate, is necessary to obtain small composition tunable alloys. This new route and insights will provide guidelines for the wet-chemical synthesis of yet unmade bimetallic alloy nanoparticles. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11051-012-0991-5) contains supplementary material, which is available to authorized users.  相似文献   
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