Correction: Magnetic properties of the seven-coordinated nanoporous framework material Co(bpy)1.5(NO3)2 (bpy = 4,4'-bipyridine).

Correction for 'Magnetic properties of the seven-coordinated nanoporous framework material Co(bpy)1.5(NO3)2 (bpy = 4,4'-bipyridine)' by Elena Bartolomé et al., Dalton Trans., 2012, 41, 10382-10389.

Spin Densities in Flavin Analogs within a Flavoprotein.

Characterization by electron paramagnetic resonance techniques of several variants of Anabaena flavodoxin, where the naturally occurring FMN cofactor is substituted by different analogs, makes it possible to improve the details of the spin distribution map in the isoallosazine ring in its semiquinone state. The analyzed variants were selected to monitor the effects of intrinsic changes in the flavin ring electronic structure, as well as perturbations in the apoflavodoxin-flavin interaction, on the spin populations. When these effects were analyzed together with the functional properties of the different flavodoxin variants, a relationship between spin population and biochemical parameters, as the reduction potential, could be envisaged.

Magnetic properties of the seven-coordinated nanoporous framework material Co(bpy)1.5(NO3)2 (bpy = 4,4'-bipyridine).

The magnetic properties of the porous metal-organic complex Co(bpy)(1.5)(NO(3))(2) (bpy = 4,4'-bipyridine), investigated by SQUID magnetometry, EPR and heat capacity measurements, are reported. The tongue-and-groove structure of this complex is formed by the assembly of T-shaped building blocks, where each Co is bound to three bpy ligands. Co(II) is hepta-coordinated by three N atoms from the bpy units, and four O atoms from two nitrate groups. Experimental results showed a large crystal field effect induced anisotropy with a zero field splitting of Δ = 198 K between the ground and excited Kramers doublets, a factor of two larger than previously reported values in Co(II) hepta-coordinated complexes. EPR revealed orthorhombic crystal field anisotropy, with gyromagnetic principal values of g(1)* = 6.1, g(2)* = 4.2 and g(3)* = 2.2, in an S* = 1/2 effective spin on the ground state Kramers doublet. Ab initio simulations allowed us to assign the anisotropy easy axis of magnetization to the binary symmetry axis of the molecule, aligned with the Co-N apical direction of the T-block.