Structural, Magnetic and Dynamic Characterization of Liquid Crystalline Iron(III) Schiff Base Complexes with Asymmetric Ligands

Abstract

The iron(III) complexes that were formed by coordination of the Fe III ion with the asymmetric tridentate liquid crystalline Schiff base ligand (L), the water molecules and the different counterions [PF 6 -(1), NO 3 -(2), and Cl -(3)] were studied by electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy demonstrated that each of the complexes investigated consists of two types of iron centers: S = 1/2 low-spin (LS) and S = 5/2 high-spin (HS). LS iron complexes 2, 3 and LS complex 1 in the temperature range 4. + X -, with X = PF 6 -as the counterion. The LS and HS iron centers of 1 are coupled together antiferromagnetically and form a dimer structure by means of the water molecules and the PF 6 -counterion. The second-type of LS and HS cen-

Pentacoordinated Chloro-Iron(III) Complexes with Unsymmetrically Substituted N2O2 Quadridentate Schiff-Base Ligands: Syntheses, Structures, Magnetic and Redox Properties

“…118.33 (18) The principal structural features of complexes 3 and 5 are depicted in Figure 2. The two structures consist of discrete molecules of [Fe(L A /L D )Cl].…”

Grafted iron(iii) ions significantly enhance NO2 oxidation rate and selectivity of TiO2 for photocatalytic NOx abatement

“…The resonances at g ¼ 9.678, 6, 4.286 and the broad background signal are indicative of high spin Fe(III), 6 S 5/2 ground term (5 unpaired electrons). 35,36 A detailed analysis of these gvalues is provided in the ESI. † The almost isotropic resonance at g ¼ 4.286 is oen found in strong (D > hv) low symmetry (E/D z 1/3) crystal eld.…”

“…† The almost isotropic resonance at g ¼ 4.286 is oen found in strong (D > hv) low symmetry (E/D z 1/3) crystal eld. 35,36 This indicates that the iron is most likely present on the surface of the TiO 2 and in either very small clusters or isolated ions, since a location inside the bulk of a crystal lattice (of either TiO 2 or an iron oxide cluster) would be high symmetry.…”

Synthesis, Crystal Structures and Preliminary Antibacterial Activities of Nickel(ii) and Zinc(ii) Complexes Derived From 2-Bromo-6-[(3-Cyclohexylaminopropylimino) Methyl]phenol

“…Calcd. for C 16 Crystal Structure Determination: Diffraction intensities for complexes (1) and (2) were collected at 298(2) K using a Bruker APEX II area-detector with CuKa and MoKa radiation, respectively. The collected data were reduced using SAINT program, 14 and multi-scan absorption corrections were performed using SADABS program.…”

“…[1][2][3] Schiff bases derived from the condensation of salicylaldehyde with primary amines represent an important class of chelating ligands, the metal complexes of which have been widely studied. [4][5][6][7][8][9] A detailed search of literature indicates that only two ruthenium complexes, 10 three zinc complexes, 11,12 and one titanium complex 13 with the Schiff bases derived from 3-bromosalicylaldehyde have been reported so far.…”