EPR Evidence For Magnetic Exchange Through a Four-Carbon Aliphatic Bridge in a Binuclear Copper(II) Complex. Single Crystal X-Ray Structure of 7, 7′-(1, 4-Butanediyl)-Bis{2,12-Dimethyl-3,7,11,17-Tetraazabicyclo[11.3.1]Heptadeca-1(17),2,11,13,15-Pentaene)Nickel(II)} Perchlorate Monohydrate
| Autor: | Keith A. Foster, Donald G. Van Derveer, Mark D. Timken, E. Kent Barefield, R. Linn Belford, David R. Brown |
|---|---|
| Rok vydání: | 1988 |
| Předmět: |
Chemistry
Stereochemistry chemistry.chemical_element Crystal structure Copper law.invention Nickel Crystallography Perchlorate chemistry.chemical_compound law X-ray crystallography Materials Chemistry Physical and Theoretical Chemistry Electron paramagnetic resonance Single crystal Monoclinic crystal system |
| Zdroj: | Journal of Coordination Chemistry. 19:123-137 |
| ISSN: | 1029-0389 0095-8972 |
| Popis: | The single crystal x-ray structure of the title, binuclear nickel(II) complex has been determined and the compound used as a host for EPR investigations of the analogous copper(II) complex. The impetus for this work was an earlier suggestion that magnetic exchange interactions detected by EPR spectroscopy on frozen solutions of the biscopper(II) complex were a result of a direct copper-copper interaction in a “closed” conformation of the binuclear species. Results reported here suggest that the complex exists in the open conformation where the distance between metal centres is maximized and that the magnetic exchange occurs by a super-exchange mechanism through the aliphatic chain. The │J│ value for the exchange interaction is greater than 0.018 cm-1. Crystal data for [Ni2(C34H50N8](CIO4)4-H2O(298 K): monoclinic, space group P21/n, a = 13.560(3), b = 11.678(2), c = 15.377(3) A, β = 108.48(2)°, ρcaled = 1.588 g cm-3 for Z = 2 and M r = 1104.1, R = 0.068, R w = 0.076. The intramolecular Ni-Ni distance is 9.... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|