Structural and spectroscopic properties of metal-urea complexes

Influence of various organic molecules on the reduction of hexavalent chromium mediated by zero-valent iron.

https://pubs.rsc.org/en/content/articlepdf/2017/cc/c6cc08618g

Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(II) complexes

Synthesis, structure and Mössbauer characterization of polymeric iron(II) complexes with bidentate thiourea ligands

Cooperative Metal–Ligand Reactivity and Catalysis in Low-Spin Ferrous Alkoxides

Mössbauer characterization of some new high-spin iron complexes with urea and thiourea derivatives

Urea (ur), thiourea (tu) and diisopropylthiourea (diptu) form high-spin complexes with iron(II), for which57Fe Mossbauer quadrupole splitting and spectroscopic data suggest an octahedral distorted geometry. The x-ray diffraction study on Fe(tu)4Cl2 confirms this geometry. The crystals are tetragonal, space groupP42/n witha=13.71,c=8.94 A andZ=4. The molecules are centrosymmetric with two axial chlorine atoms (Fe-Cl=2.46 A) and four equatorial sulfur atoms (Fe-S=2.61 and 2.57 A respectively). A similartrans-octahedral geometry is proposed for the new Fe(diptu)4Cl2 complex and an octahedral metal coordination in the new [Fe(ur)6]Br2, Fe(tu)3Br2 and Fe(ur)3Br2 complexes.

Characterization of some High-Spin Iron(II) Complexes with Urea Derivatives. The Crystal Structure of Dichlorotetrakis(thiourea)iron(II)

Mossbauer parameters for hexacoordinate iron(II) complexes of the type [Fe(N-N)n(CNMe)m](ClO4)2 (m = 6, 4, 2 or 0; n = 0, 1, 2 or 3; N−N = 2,′ -bipyridine or 1,10-phenanthroline) have been determined. Treatment by a point-charge model including distortions has been carried out in order to rationalize the quadrupole splittings. A computer program has been developed to handle variable geometry systems.

Sandro Calogero

Papers

Mössbauer characterization of some new high-spin iron complexes with urea and thiourea derivatives

Characterization of some High-Spin Iron(II) Complexes with Urea Derivatives. The Crystal Structure of Dichlorotetrakis(thiourea)iron(II)

A Mössbauer study of some iron(II) complexes with methyl isocyanide, bipyridine and phenanthroline