Magnetocaloric features of complex molecular magnets: The (Cr7Ni)2Cu molecular magnet and beyond

Magnetic entropy change plateau in a geometrically frustrated layered system: FeCrAs-like iron-pnictide structure as a magnetocaloric prototype

“…So far several systems have been found to exhibit MCE at room temperature [1][2][3][4][5][6], generating tremendous expectations for refrigeration and other applications [1][2][3][4][5][6]. There is a wide range of further applications for MCE, for instance, gas liquefaction [1,3], space technologies [7] or tumor-targeting magnetic materials [8], and recently molecular materials have proved to be systems where the understanding of the MO would have a very profound impact [9][10][11][12].…”

“…Although this last approach has been extensively exploited in the last few years the fact that the transitions are usually of first order and that those which are second order occur only within very narrow temperature regimes, gives a strong MCE over only a small temperature range. To locate the maximum value of a MO at a certain working temperature, the peak singularity or the continuous-derivative peak of the observable has to be temperature-shifted, and this has been accomplished only for some families of compounds [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”

Thermal observables in coupled Cr7Ni molecular rings: Role and quantification of spin-entanglement

“…V C 2011 American Institute of Physics. 12 However, the quantification of quantum entanglement in microscopic systems still requires further research, 13 and spin-entanglement in molecular magnets is a promising topic of research due to its possible implications in the context of molecular electronics. 1,2 Among the newest molecular magnets, there is an interesting group in the family of the molecular Cr 7 Ni-based magnets, e.g., the Cr 7 Ni-Cu-Cr 7 Ni, 3 the Cr 7 Ni-purple, and the Cr 7 Ni-green.…”

“…1,2 Among the newest molecular magnets, there is an interesting group in the family of the molecular Cr 7 Ni-based magnets, e.g., the Cr 7 Ni-Cu-Cr 7 Ni, 3 the Cr 7 Ni-purple, and the Cr 7 Ni-green. 12,[14][15][16] Other studies have shown that low-temperature antiferromagnetic coolers have proved to be more efficient than the ferromagnetic ones as a consequence of the magnetic entropy difference behavior, which displays a maximum at low temperature as a function of the magnetic field. 3,4,6 Moreover, Cr 7 Ni-based magnets have recently been added to the growing list of molecular magnets that would possibly retain their magnetic properties after being grafted or wired to conducting surfaces.…”

“…12 Now, the bipartite entanglement or entanglement of formation associated with the density matrix q of our system is addressed by calculating E f ðq Cu Þ ¼ eðC½q Cu Þ, 19 where eðCÞ ¼ R Spin operators are jS A j ¼ jS B j ¼ jS C j ¼ 1 2 , and g ef ¼ g A ¼ g B and g C are taken from experimental results.…”