Slow magnetic relaxation

Slow Magnetic Relaxation and Phonon Bottleneck Effects... 

At the beginning of this century slow magnetic relaxation in the paramagnetic phase of a ID system was reported for a Co2+ nitronyl-nitroxide chain [58]. The dynamics was under many respects very similar to that of SMMs and these ID systems were later named SCM to underline the analogies [9]. Since then an intense research activity, though not as spread out as for SMMs, has been devoted to SCMs. The interested reader can find extensive literature on the subject, including exhaustive reviews and a book chapter [59-63]. The aim here is to provide some basic concepts of the phenomenon and to introduce some selected examples of SCMs based on lanthanide ions. 

To ensure that the slow magnetization relaxation is an intrinsic molecular property, the measurement could be carried out for a sample diluted in a diamagnetic matrix. Indeed [TbPc2] and [DyPc2] compounds were investigated along with... 

Table 8.2 Characteristic parameters of the slow magnetization relaxation observed in [LnPc2]-/0/+ complexes.

Gao, S., Su, G, Yi, T., and Ma, B. (2001) Observation of an unusual field-dependent slow magnetic relaxation and two distinct transitions in afamily of rare-earth-transition-metal complexes. Physical Review B Condensed... 

From the middle of 1990s, various metal clusters having slow magnetic relaxation time have been reported as single-molecule magnets (or superparamag-nets) [26] and spin glasses [27]. These have become a current topic in molecular... 

Alternating current (ac) magnetic susceptibility measurements in zero dc field allow to probe slow magnetization relaxation indicating SMMs behaviour. The applied oscillating held probes the dynamics of this reorientation, as the out-of-... 

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