Presence of Jahn-Teller distortions in a novel six-coordinate Ag(II) complex: temperature dependent EPR, optical and magnetic susceptibility measurements
| Autor: | Kundu, T.K., Manoharan, P.T. |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Magnetic variables measurement
Silver Magnetic susceptibility measurement Optical properties Jahn-Teller distortions Temperature Biophysics Condensed Matter Physics Magnetic properties Single crystals Optical variables measurement Physical and Theoretical Chemistry Molecular physics Infrared spectroscopy Paramagnetic resonance Molecular Biology |
| Zdroj: | Molecular Physics. 98:2007-2019 |
| ISSN: | 1362-3028 0026-8976 |
| DOI: | 10.1080/00268970050199752 |
| Popis: | Single-crystal variable temperature EPR, optical and polycrystalline magnetic susceptibility studies have been made on a novel six-coordinate Ag(II) complex. Temperature dependent EPR studies on pure single crystals of this compound reveal that dynamic Jahn-Teller distortion operates above 230 K, between 230 K and 120 K static Jahn-Teller distortion sets in and below 110 K there is evidence of exchange interaction. Crystal g values were obtained by least-squares fitting with the data obtained from the orientation dependent EPR spectra of the undiluted single crystal of this complex at 300 K and 77 K. From an optical study the Jahn-Teller stabilization energy is found to be ?2250 cm-1. Comparison of Absmax values for other silver(II) compounds enables us to conclude that the formal geometry of this complex is a tetragonally distorted octahedral. Infrared spectra of this complex were also recorded over a wide range of temperature. Magnetic susceptibility measurements over a wide range of temperature on the powder sample of this compound reveal that the complex is antiferromagnetically coupled in the temperature range 5-40 K with 2J = 0.906 cm-1, and above 40 K it is ferromagnetically coupled with 2J = +7.4 cm-1. The effective magnetic moment (?eff) of this complex has been compared with that of a series of other silver(II) complexes available in the literature. Finally, the spectral and magnetic data of this complex have been compared with those of a corresponding isostructural and isomorphous copper(II) complex. |
| Databáze: | OpenAIRE |
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