Magnetic complex

Conductive Materials Based on M(dmit)2 Complexes and Their Combination with Magnetic Complexes... 

Only three general reviews on vanadium(IV) complexes have been given 355-357 others deal with subnormal magnetic complexes,358 ESR spin probes,354 vanadium(IV) halides,6 optical spectra and phosphorus donor ligands,359 vanadium porphyrins128 and annual reviews for 1979, 1980 and 1981. 

The temperature dependence of the magnetic complex conformation is known to be one of the distinguishable features of Jahn-Teller (JT) dynamics [1]. Keeping in mind electron paramagnetic resonance (EPR) as one of the most effective methods of studying the JT effect, we shall consider the problem of the transition from the low temperature, static JT situation to the high temperature, dynamic, motional averaged JT situation. The results of such processes are discussed in the literature [1-4]. At the same time, some important features - the nature of the transitions... 

In the case of covalency in a magnetic complex, charge transfer from ligand to partially filled metal orbitals results in a transfer of spin density in the opposite direction. The magnitude of the spin transfer, obtainable from LHFI, is directly related to the covalency parameters by the simple MO model (see Section II. B). 

The resolved, hyperfine-shifted pmtions of the H NMR spectra of Tl and Pf 3Fe Fd° (Fig. BA) are similar to that of the 3Fe Fd from mesophilic H NMR spectra for hyperthermostable 3Fe FrP have not been reported. The three cluster ligated Cys have been identified in both 77 and Pf 3Fe Fd, with one Cys exhibiting Curie, and two Cys displaying anti-Curie behavior, as shown in Fig. 15 for the latter protein, consistent with the magnetic complex of a 5 = 2 diferric pair with a single ferric S = 5/2. The unique Cys in the three Fd, however, is not at the same position in the consensus ligating sequence. " The structural basis for the unique iron is not understood. 

SCHEME 9.R.4 Different electron occupancy patterns when there are six electrons in the d-orbitals in the case of a large splitting gap (left) versus a small splitting gap (right). When the gap is small, four of the electrons occupy solo four of the d-orbitals and form a high-spin magnetic complex with four identical (parallel) unpaired spins. 

In case of trigonal symmetry, the is not split. However, the orbital degeneracy is lifted by the Jahn-Teller effect which, at higher temperatures, might distort the molecular complex. At lower temperatures, the Jahn-Teller distortion in some cases goes over into a static distortion, and a spectrum due to three magnetic complexes, each with tetragonal symmetry may be observed [53]. 

CsA1(S04)2 I2H2O, cubic, point group Th=(2/m)3 f) type alumn Z=4 C.S. 3, C.S.4 V—0 axes displaced from the crystallographic axes 12 different magnetic complexes VOlHjO) ... 

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