An EXAFS, and preliminary X-ray crystallographic, investigation of an iron-containing product from the lichen Cladonia deformis.
An iron-containing product in the acetone extract from the lichen Cladonia deformis has been investigated using chemical, spectroscopic and X-ray crystallographic methods. Visible-near UV, EPR and IR spectra indicate that the iron is present as high-spin Fe(III) and coordinates in an oxygen-containing environment arising from graciliformin (or graciliformin-like) ligands. This has been confirmed by an XAS (X-ray absorption) study using synchrotron radiation. Comparison of the EXAFS and XANES results with those obtained from a model, tris(pent-2,4-dionato)Fe(III), and detailed fitting using the single-scattering, curved-wave formalism for the EXAFS strongly supports the presence of a Fe(III) coordinated to five oxygen atoms from the graciliformin.
Alagna
L
L
I.T.S.E., Area della Ricerca di Roma, C.N.R., Italy.
Prosperi
T
T
Tomlinson
A A
AA
Kjøsen
H
H
Mo
F
F
D007501:Iron / Q000032:analysis*; D008011:Lichens / Q000032:analysis*; D013057:Spectrum Analysis; D014961:X-Ray Diffraction
D007501:Iron