Characterization of the 18-crown-6-lanthanum(III) complex in methanol using 139La nuclear magnetic resonance
| Autor: | Christian Detellier, Heather Dettman, Zhigang Chen |
|---|---|
| Rok vydání: | 1989 |
| Předmět: |
chemistry.chemical_classification
Coordination sphere Chemical shift 18-Crown-6 Inorganic chemistry chemistry.chemical_element Nuclear magnetic resonance spectroscopy Inorganic Chemistry Crystallography chemistry.chemical_compound chemistry Materials Chemistry Lanthanum Macrocyclic ligand Physical and Theoretical Chemistry Equilibrium constant Crown ether |
| Zdroj: | Polyhedron. 8:2029-2033 |
| ISSN: | 0277-5387 |
| DOI: | 10.1016/s0277-5387(00)80499-4 |
| Popis: | The complex formed between LaCl 3 ·7H 2 O and the macrocyclic ligand 18-crown-6 (18C6) in methanol has been characterized by 139 La NMR. Two sites in very slow exchange on the 139 La NMR chemical shift time scale coexist in methanolic solutions: solvated and 1 : 1 complexed 139 La III . Both chemical shift and relaxation rate data point to the participation of the chloride counteranion and of the crown ether in the first coordination sphere of lanthanum(III). The equilibrium constant of formation of the complex, determined from the populations of the two 139 La NMR sites, is in excellent agreement with previously determined data from the literature. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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