Magnetically coupled complex

Bridged or Through-space Magnetically Coupled Complexes of High-spin Iron(III) Porphyrins with Other Types of Metal Complexes Possible Models for Cytochrome Oxidase, Assimilatory Sulfite Reductases, and Sulfite Oxidase... 

A species of this type is probably best described as a [Fe - NO ] complex, with a resultant spin S = 3/2 characteristic of a shongly magnetically coupled complex. Magnetically coupled systems exhibiting the combined influence of and an electrostatic interaction termed Heisenberg exchange are discussed in Section 4.5. 

Band L, Bencini A, Benelli C, Gatteschi D, Zanchini C (1982) Spectral-Structural Correlations in High-Spin Cobalt(II) Complexes. 52 37-86 Band L, Bertini I, Luchinat C (1990) The H NMR Parameters of Magnetically Coupled Dimers-The Fe2S2 Proteins as an Example. 72 113-136 Baran EJ, see MuUer A (1976) 26 81-139... 

A Family of Asymmetric [Ln2] Complexes with Weak Magnetic Coupling... 

Very recent calculations within the unrestricted ZORA-SORCI formalism on complexes indicated the neutral fe(l,2-dithiolene) complexes as consisting of two S,S-coordinated n radical monoanions strongly antiferro-magnetically coupled via the central diamagnetic Mn ion with a not negligible diradical character. In this context, the low-energy NIR transition should be considered as a LLCT band. See ref. 53. 

SCO Cationic Complexes Encapsulated in Magnetically Coupled Anionic Networks... 

The present status of attempts to encapsulate SCO complex cations in magnetically coupled anionic frameworks was described in Sect. 3. To date, there is no evidence for magnetic or cooperative interactions between cation and host network, for the anionic oxalato or dicyanamido types. 

We have seen that copper(II) is a slowly relaxing metal ion. Magnetic coupling of copper to a fast relaxing metal ion increases the electron relaxation rate of copper, as clearly shown by the NMRD profiles of tetragonal copper(II) complexes reacting with ferricyanide (105) (Fig. 38). The electron relaxation time, estimated from the relaxation rate of the water protons coordinated to the copper ion, is 3 x 10 ° s, a factor of 10 shorter than in the absence of ferricyanide. 

The Fe(III)-NO complex of NPl is EPR silent (Fig. 3) because it contains an odd-electron (ferriheme) center bound to the odd-electron diatomic NO 24), which creates a FeNO center. The NMR spectrum of NPl Fe(III)-NO is that of a diamagnetic protein 85). However, whether the electron configuration is best described as Fe(II)-NO+ or antiferro-magnetically coupled low-spin Fe(III)-NO- is not completely clear, even though the infrared data 49) discussed earlier (Fig. 7) are consistent with the former electron configuration. Thus, as a prelude to planned detailed studies of the Mossbauer spectra of the nitrophorins and their NO complexes, we have reported the Mossbauer spectrum of the six-coordinate complex of OEPFe(III)-NO 86). 

However, magnetic coupling behavior may be more complex to model than possible with a simple isotropic Heisenberg Spin Hamiltonian as defined in Eq. (79) and several recent studies set out to improve this description by modification of this Hamiltonian (86-89). 

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