merging classical and quantum behavior in a nanosized object. [1][2][3][4] From the applicative point of view, the use of magnetic molecules in spintronics can offer several advantages due to different aspects. On one side, molecular magnets have the functionality of carrying magnetic information down to the molecular size. This encourages the race toward miniaturization of magnetic devices as well as the exploitation of magnetic molecules for quantum computing, [5] although this solution is still hindered by the low working temperature. [6][7][8] On the other side, nonmagnetic molecular materials like organic semiconductors (OSCs) have been considered rather extensively during the past decade in the search for optimal combinations for prototypical devices in the area of spintronics technology, i.e., spin-valves. [9] The magnetoresistance in such devices, which consist of ferromagnetic metal electrodes sandwiching a semiconducting material, depends on the injection and transport of the spin through the semiconductor spacer. OSCs typically possess weak spin-orbit coupling and, because of this, they guarantee longer spin coherence time compared to both inorganic semiconductors and metals. In this context, different organic materials, such as pentacene [10] and tris(8-hydroxyquinoline) aluminium(III) (Alq 3 ) [11,12] and the gallium(III) analogue (Gaq 3 ), [13] have been employed in combination with several ferromagnetic metals, such as Fe and Co:TiO 2[10] or Co and La 0.7 Sr 0.3 MnO 3 (briefly termed LSMO). [11,12] The changes of physical properties of both the metal and organic molecule at the interface have also attracted great scientific interests, so that the ad hoc term spinterface [14,15] has been advanced to describe the topic. From the organic side the spinterface describes the spin filtering effects caused by the spin-dependent hybridization of the organic and metallic orbitals, leading to different interfacial broadening (and hence transmissivity) of the localized organic states for the two spin channels. [14] On the other hand, it has been shown both experimentally [16] and theoretically [17][18][19] that some organic molecules can affect the magnetic properties of the underlying magnetic surface, in terms of magnitude and direction of magnetic moments and spin polarization as well as of strength of exchange interactions. Moreover, coupling between the spins of transition-metal based molecular magnets and magnetic surfaces can be obtained promoting A novel functionalization of a ferromagnetic electrode employed in spintronic devices is reported. Self-assembling monolayer technique has been used to chemisorb a paramagnetic phosphonate functionalized nitronyl-nitroxide radical (NitPO) on the ferromagnetic La 0.7 Sr 0.3 MnO 3 (LSMO) manganite surface. This interfacial layer causes clearly detectable modifications of the behavior in prototypical LSMO/NitPO/Gaq 3 /AlOx/Co vertical spintronic devices at temperatures below the ferromagnetic alignment (estimated by density functional theory) of the magnetic mome...

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A study of the magnetic structure of the [NH(CH)][FeM(HCOO)] niccolite-like compounds, with M = Co (2) and Mn (3) ions, has been carried out using neutron diffraction and compared with the previously reported Fe-containing compound (1). The inclusion of two different metallic atoms into the niccolite-like structure framework leads to the formation of isostructural compounds with very different magnetic behaviors due to the compensation or not of the different spins involved in each lattice. Below T, the magnetic order in these compounds varies from ferrimagnetic behavior for 1 and 2 to an antiferromagnetic behavior with a weak spin canting for 3. Structure refinements of 2 and 3 at low temperature (45 K) have been carried out combining synchrotron X-ray and high-resolution neutron diffraction in a multipattern approach. The magnetic structures have been determined from the difference patterns between the neutron data in the paramagnetic and the magnetically ordered regions. These difference patterns have been analyzed using a simulated annealing protocol and symmetry analysis techniques. The obtained magnetic structures have been further rationalized by means of ab initio DFT calculations. The direction of the magnetic moment of each compound has been determined. The easy axis of the M for compound 1 (Fe) is along the c axis; for compound 2 (Co), the moments are mainly within the ab plane; finally, for compound 3 (Mn), the calculations show that the moments have components both in the ab plane and along the c axis.

We report first-principles predictions of magnetoelectric coupling in organic magnetic helices and clarify the microscopic mechanism of spin-induced electric polarization.