Three-Dimensional Magnetic Materials

Blue itself has the formula (Fe )4[Fe (CN)6]3 xH20 and is a ferro-magnet below 5.6 K. In this case, only the Fe sites contribute to the spin the Fe cation in a strong ligand field is diamagnetic, but mediates the communication between the magnetic centres. 

2H2O were discovered by Entley and Girolami to order at 125 K and 230 K, respectively.[Cr5(CN)i2] 10H2O and Cso.75[Cr2.i25(CN)6] 5H2O were made by Mallah et al. and observed to order at 240 K and 190 K, respectively, The culmination of this effort, in terms of moving to 

To prepare additional examples, the identity of the transition metal has been varied with modest success. Miller et al. have reported M(TCNE)2 species based on replacing by Mn, Fe , Co and Ni that exhibit ordering, albeit at lower temperatures, though still above 100 Casellas et al. have extended this list to include a vapour-phase 

Miller et al. have also synthesised two rare earth analogues based on TCNE and Gd and Dy. The former is a spin-only ion and the latter has the highest possible value of /. These solids are ferrimagnets with Tcs of 3.5 K and 8.5 K, respectively. 

The series of compounds in Table 3.3 is an example of the utility of synthetic organic chemistry for preparing systematically related building blocks that exhibit interesting trends in bulk magnetic properties. The compounds are all easily synthesised from the corresponding benzalde-hydes in moderate yield. High Tq is favoured by substitution in the 2- and 

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Below the three-dimensional ordering temperature, one-dimensional materials are expected to behave in a manner similar to three-dimensional magnetic materials. Table III. Figure 21 illustrates the temperature dependence for the ideal three-dimensional paramagnet, ferromagnet, and antiferromagnet (129, 293). The transitions at the Curie temperature, Tc, and the Neel temperature, Tjv, are also marked, in particular, by changes in the temperature-dependent specific heat. 

TEMPERATURE DEPENDENCE OF SUSCEPTIBILITY FOR THREE-DIMENSIONAL MAGNETIC MATERIALS ... 

Most of the conducting or magnetic materials investigated in the homoleptic series are salts while many of the radical heteroleptic complexes described above are in their neutral state, potentially allowing for a stronger three-dimensional character. 

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