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101.
B. Lorenz R. Kirmse M. Findeisen K. Schmidt 《Isotopes in environmental and health studies》2013,49(1):125-130
Abstract The reaction of 2-pyridine carboxylic acid (Hpic) with (n-Bu4N)[TcNCl4] and (n-Bu4N)[TcOCl4] in ethanol and methanol, respectively, yields the dinuclear μ-oxo complex [(pic)2NTc-O-TcN(pic)(Hpic)Cl] and the monomeric complex [TcO(pic)2Cl]. Visible and infrared spectroscopy, ESR, 1H-NMR and 99Tc-NMR have been used to characterize the new compounds. The most important field of application for the new compounds synthesized is radiodiagnostics. 相似文献
102.
合成了一种新配体N,N-二[(二苯基膦)甲基]-2-吡啶胺(L)及其双核铜(Ⅰ)配合物(CuBrL)2(1),采用1HNMR、吸收光谱、质谱和元素分析等方法对化合物进行表征,并通过X射线单晶衍射确定配合物1的晶体结构。该晶体结构属三斜晶系,P-1空间点群。配合物1是中心对称的双核Cu(Ⅰ)配合物,中心离子Cu(Ⅰ)采取扭曲四面体空间构型,分别与配体L的两个P原子和两个桥联的Br原子配位;其中Cu-Cu距离为0.3060nm,大于两个铜原子的范德华半径之和,因此不存在Cu-Cu相互作用。密度泛函理论(DFT)计算表明1的HOMO电子密度主要集中于铜和卤素原子,而LUMO电子密度分布在配体(L)上。研究工作表明,配合物1的最低能级激发态通过金属到配体电荷跃迁(MLCT)和卤素到配体的电荷跃迁(XLCT)两种机制形成。 相似文献
103.
104.
Highly emissive Re(I) complexes, hydrophobic cis-Re(CO)2(c-dppene)(dpphen) and water-soluble cis-Re(CO)2(c-dppene)(SO3-dpphen) with a negative charge, were synthesized [where c-dppene is cis-(bis(diphenylphosphino)ethylene, dpphen is 4,7-diphenyl-1,10-phenanthroline, and SO3-dpphen is its disulfonate derivative]. These Re(I) complexes have significantly higher molar absorption in the 350- to 490-nm region compared to their tricarbonyl Re(I) counterparts and their emission spectra are similar to those of Ru(II) polypyridyl complexes. The luminescence lifetimes of these Re(I) complexes approach 10 s in the absence of oxygen in both aqueous and less polar solvents. The complexes have limiting anisotropy values exceeding 0.3. As both ligands, the diimine and the bidentate phosphine, can be modified by adding different substituents, it should be possible to make cis-Re(CO)2(diimine)(P-P) derivatives which are capable of labeling biomacromolecules for biochemical and biophysical studies. 相似文献
105.
利用紫外-可见、近红外及中红外光声光谱对钕配合物的激发态能级状况、驰豫过程,荧光性质进行探讨,并深入研究了钕离子和配体对彼此光声谱峰移动和峰强度的影响。 相似文献
106.
We report combinatorial molecular beam epitaxy synthesis and properties of a ternary epitaxial film of Co and Mn co-doped Ge grown on Ge (0 0 1) substrate. Structural effects were examined in situ by reflection high-energy electron diffraction and ex situ by microbeam X-ray diffraction techniques, and magnetic properties were probed by using magnetooptic Kerr effect. Ternary epitaxial phase diagrams have been studied for total doping concentrations up to 30 at.%, where regions of coherent epitaxy and rough disordered growth and those of near room temperature ferromagnetic ordering have been identified. 相似文献
107.
The UV spectra of some chlorinated o-hydroxyschiff bases were studied in different solvents. It was found that schiff bases derived from condensation of 2-hydroxybenzaldehyde or 5-chloro-2-hydroxy benzaldehyde with substituted aniline exist as enol form, whereas schiff bases derived from the condensation of 3,5-dichloro-2-hydroxybenzaldehyde with substituted aniline exist as enol form, whereas schiff bases derived from the condensation of 3,5-dichloro-2-hydroxybenzaldehyde with aniline exist as keto form especially in dimethyl sulfoxide. The ratio of enol/keto isomers were calculated for these schiff bases. 相似文献
108.
The linear and nonlinear optical properties of two metalloporphyrin complexes formed by the complementary coordination of central zinc or magnesium ions to the ligand 5, 10, 15-tri-(p-tolyl)-20-phenylethynylporphyrin are theoretically investigated by using the analytic response theory at the density functional theory level. The results indicate that the studied complexes present more symmetric geometry structures than the ligand. The charge-transfer states of the two complexes in the lower energy region are all almost degenerate but those of the ligand are well separated. The ratio of the two-photon absorption cross sections of the ligand, zinc-porphyrin and magnesium-porphyrin complexes is 1.0:1.5:1.8, demonstrating that the two-photon absorption capability can be greatly increased when the ligand is coordinated with a metal ion. Moreover, several physical micro-mechanisms including electron transitions and intramolecular charge-transfer processes are discussed to explore the differences in optical property between the ligand and two complexes. 相似文献
109.
110.
For the fast characteristics of mixtures of Aluminium, Gallium and Indium the fluorimetric evaluation in the form of complexes
with 8-Hydroxyquinoline-5-sulphonic acid is described at selected pH. The highly collinear correlated fluorescent spectra
and their first derivation were evaluated under various experimental conditions with the Multiple Linear Regression (MLR),
Partial Least Squares (PLS) methods and Kalman filtering. When comparing the results, the PLS gives the least relative prediction
errors under optimal conditions, 5.6–15.9% for the concentration range of Al 0.025–0.2 μg cm−3, Ga 0.1–0.8 μg cm−3 and In 0.1–0.8 μg cm−3 in the mixture. 相似文献