Magnetization, temperature-dependent

The electrocrystallization and characterization of a novel molecular metal which displays both electronic and ionic conduction has been reported. The complex Li0.6(15-crown-5-ether)[Ni-(dmit)2] H20 is composed of stacks of [Ni(dmit)2] units which provide pathways for electronic conduction. The stacks are separated by parallel stacks of 15-crown-5-ether moieties in a channellike formation which facilitates ion conduction. The salt has a room temperature conductivity of 240 Scm-1. Temperature-dependent magnetic susceptibility and NMR measurements were used to prove the existence of Li+ movement within the crown ether channels.1030... 

Temperature-Dependent Magnetic Susceptibility and Field-Dependent Magnetization... 

Magnetic Susceptibility and EPR Data. The temperature dependent magnetic susceptibility and EPR of the S -ethylporphyrazines were measured and the effective magnetic moments ([teff), spin, and J values are reported in Table XIV (113, 116). 

In the Mossbauer spectra of the Fe(R2Dtc)3 complexes, simple quadruple split doublets are observed that are interpreted as the weighted means of the high-spin and low-spin forms (153). It has been pointed out (454) that a rapid transition (>10 7 sec) is not characteristic for complexes with different spin states, and indeed two doublets are observed in the Mossbauer spectra of iron(II) compounds with temperature-dependent magnetic moments. The same... 

Nelson and coworkers187 have synthesized a series of mixed-ligand iron(II) complexes of the type [Fe(dippen)2X2], where dippen is cis-l,2-bis(diphenylphosphino)-ethylene, and X = Cl-, Br-, NCS-, and NJ. Temperature dependent magnetic sus-... 

The effect of intraligand substitution on the spin crossover behaviour in these systems has been further investigated using various techniques188). Variable temperature Mossbauer spectra show the quadrupole doublets of the two coexisting spin states. Thermodynamic parameters have been derived from the temperature dependent magnetic susceptibility data. AH has been found to be 4.8,3.1, and 4.8 kcal mol-1 for II, III, and IV, serially, in the solid state, and 4.6 and 2.8 kcal mol-1 for II and III, respectively, in solution. 

The first enzyme investigated by MCD was DMSOR where the Mo center is the sole chromophore (113). The Mo(V) state of DMSOR is formed only in substoichiometric amounts, making it impossible to study its features by electronic spectroscopy or MCD. An inactive, glycerol-inhibited form of the enzyme trapped in the Mo(V) state, which was robust under the required experimental conditions, was studied instead. The resultant MCD spectrum consisted of six transitions whose behavior (temperature dependence, magnetization) mapped precisely onto the expected six transitions of a dithiolene chelated to Mo. These results were duplicated for the tungsten enzyme AOR in Pfuriosus (114). However, note that the interpretation of these results was based on the (then) prevailing hypothesis that DMSOR was a mowomolybdopterin... 

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