Mössbauer, vibrational spectroscopic and solution X-ray diffraction studies of the structure of iron(III) complexes formed with indole-3-alkanoic acids in acidic aqueous solutions

Krisztina Kovács, Alexander A. Kamnev, János Mink, Csaba Németh, Erno Kuzmann, Tünde Megyes, Tamás Grósz, Hedvig Medzihradszky-Schweiger, Attila Vértes

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

The chemical reactions between iron(III) and indole-3-acetic (IAA), -propionic (IPA), and -butyric (IBA) acids were studied in acidic aqueous solutions. The motivation of this work was that IAA is one of the most powerful natural plant-growth-regulating substances (phytohormones of the auxin series). Mössbauer spectra of the frozen aqueous solutions of iron(III) with indole-3-alkanoic acids as ligands (L), showed parallel reactions between Fe3+ and the ligands. Partly, it resulted in a complex formation which precipitated in aqueous solution and partly, in a redox process with iron(II) and the oxidised indole-3-alkanoic acids as products. The Mössbauer parameters of the Fe2+ species suggested a hexaaquo coordination environment. The chemical composition and coordination structure of the precipitated complexes were investigated using elemental analysis, Mössbauer spectroscopy, Fourier transform infrared (FTIR) and Raman spectroscopic techniques. The complexes were soluble in some organic solvents. So, Mössbauer, FTIR and solution X-ray diffraction measurements were carried out on the solution of complexes in acetone, hexadeutero acetone and methanol, respectively. The data obtained supported the existence of the μ-dihydroxo-bridging structure of the dimer: [L2Fe<(OH) 2>FeL2] (where L is indole-3-propionate, -acetate or -butyrate).

Original languageEnglish
Pages (from-to)105-120
Number of pages16
JournalStructural Chemistry
Volume17
Issue number1
DOIs
Publication statusPublished - Feb 1 2006

Keywords

  • Fourier transform Raman spectroscopy
  • Fourier transform infrared (FTIR) spectroscopy
  • Indole-3-alkanoic acids
  • Iron(III) complexes
  • Moessbauer spectroscopy
  • Solution X-ray diffraction
  • Structure elucidation

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Mössbauer, vibrational spectroscopic and solution X-ray diffraction studies of the structure of iron(III) complexes formed with indole-3-alkanoic acids in acidic aqueous solutions'. Together they form a unique fingerprint.

  • Cite this