De, Dilip Kumar and STHANAPATI, J. and GHOSHAL, A. K. and PAL, A. K. (1982) Electron Paramagnetic Resonance Study of Copper(II) Fluosilicate Hexahydrate. JOURNAL OF MAGNETIC RESONANCE, 47. pp. 181-186.
![[img]](http://eprints.covenantuniversity.edu.ng/style/images/fileicons/application_pdf.png) |
PDF
Download (206kB) |
Abstract
An electron paramagnetic resonance study was performed on single crystals of copper fluosilicate hexahydrate. EPR signals correspond to three tetragonally distorted pctahedral Cu(II) ions (A site) with g values: g11 = 2.390, gJ. .= 2.093, and ·one regular octahedral Cu(II) ion (B site) with g = 2.093. The spectra are thus quite different from those observed earlier by Bleaney and Ingram in Cu(II):ZnSiF6 • 6H20. Fluosilicate hexahydrates of divalent metals belong to a series of crystals wellsuited for X-ray, magnetic susceptibility and anisotropy, electron paramagnetic resonance, optical, and other studies (J-4). Observations of an isotropic EPR signal at 90 K and above and anisotropic EPR signals at 20 K by Bleaney and Ingram (J) in Cu:ZnSiF6 • 6H20 provided the first experimental evidence of the Jahn-Teller effect. A determination of crystal structures of this series by Ray eta/. (2, 3) has revealed that copper(II) fluosilicate hexahydrate (3), contrary to earlier belief, is not isomorphous with zinc fluosilicate hexahydrate. The structure is still rhombohedral (space group R3) with a cell four times as large as that supposed earlier. The unit cell, which has dimensions a = b = 18.18 A and c = 9.857 A, contains three magnetically nonequivalent tetragonally distorted Cu(II) · 6H20 octahedra (Cu-0(1) = 1.97 A, Cu-0(2) = 1.97 A, Cu-0(3) = 2.367 A) designated as the A sites; and one regular Cu(II) · 6H20 octahedron (Cu-0 = 2.074 A) designated as the B site. It was therefore considered of interest to study EPR in single crystals of copper fluosilicate hexahydrate with the object of unravelling the nature of the ligand fields in a crystal where two types of Cu(II) complexes coexist.
| Item Type: | Article |
|---|---|
| Subjects: | Q Science > Q Science (General) Q Science > QC Physics |
| Divisions: | Faculty of Engineering, Science and Mathematics > School of Physics |
| Depositing User: | Mrs Hannah Akinwumi |
| Date Deposited: | 22 Apr 2015 14:18 |
| Last Modified: | 22 Apr 2015 14:18 |
| URI: | http://eprints.covenantuniversity.edu.ng/id/eprint/5086 |
Actions (login required)
 |
View Item |
