X-ray diffraction and Mössbauer spectrometry studies of molecular iron compounds

• Author(s): Costa, B. F. O. ; Greneche, J. M. ; Silva, M. Ramos ; Pereira, L. C. J.
• Date: 2007
• Persistent ID: http://hdl.handle.net/10316/4364
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Trinuclear iron compounds; Mössbauer spectrometry; X-ray diffraction
• Document Type: Article
• Language: English

Description

We have synthesized two new iron complexes that have been structural and magnetically characterized: diphenylguanidinium hexafluoroferrate and hexakisvaline-oxo-triiron(III) chloride. The former crystallizes as monomers with the fluoride ions six-coordinating the Fe(II) ion. Valine iron chloride is comprised of trinuclear complexes, with a well ordered oxo-centered carboxylate core and some disordered organic ligands. The magnetization curves show a paramagnetic behavior. The Mössbauer measurements as a function of temperature show a paramagnetic behavior at 300 K with two Fe sites (one quadrupolar doublet and a broad single line). At 4.2 K, besides the quadrupolar doublet there is a magnetic component which can be attributed to a slow relaxation phenomenon associated to these samples. http://www.sciencedirect.com/science/article/B6TJM-4NRK4D4-K/1/873788c647c12dac8ebec43cdbf40f5e