Due to its inherent superior perpendicular magnetocrystalline anisotropy, the FePt in L10 phase enables magnetic storage and memory devices with ultrahigh capacity. However, reversing the FePt magnetic state, and therefore encoding information, has proven to be extremely difficult. Here, it is demonstrated that an electric current can exert a large spin torque on an L10 FePt magnet, ultimately leading to reversible magnetization switching. The spin torque monotonically increases with increasing FePt thickness, exhibiting a bulk characteristic. Meanwhile, the spin torque effective fields and switching efficiency increase as the FePt approaches higher chemical ordering with stronger spin–orbit coupling. The symmetry breaking that generates spin torque within L10 FePt is shown to arise from an inherent structural gradient along the film normal direction. By artificially reversing the structural gradient, an opposite spin torque effect in L10 FePt is demonstrated. At last, the role of the disorder gradient in generating a substantial torque in a single ferromagnet is supported by theoretical calculations. These results will push forward the frontier of material systems for generating spin torques and will have a transformative impact on magnetic storage and spin memory devices with simple architecture, ultrahigh density, and readily application.

The hexanitratolanthanate anion (La(NO(3))(6)(3-)) is an interesting symmetric anion suitable to construct the component of water-free rare-earth-metal ionic liquids. The syntheses and structural characterization of eleven lanthanum nitrate complexes, [C(n)mim](3)[La(NO(3))(6)] (n=1, 2, 4, 6, 8, 12, 14, 16, 18), including 1,3-dimethylimidazolium hexanitratolanthanate ([C(1)mim](3)[La(NO(3))(6)], 1), 1-ethyl-3-methylimidazolium hexanitratolanthanate ([C(2)mim](3)[La(NO(3))(6)], 2), 1-butyl-3-methylimidazolium hexanitratolanthanate ([C(4)mim](3)[La(NO(3))(6)], 3), 1-isobutyl-3-methylimidazolium hexanetratolanthanate ([isoC(4)mim](3)[La(NO(3))(6)], 4), 1-methyl-3-(3'-methylbutyl)imidazolium hexanitratolanthanate ([MC(4)mim](3)[La(NO(3))(6)], 5), 1-hexyl-3-methylimidazolium hexanitratolanthanate ([C(6)mim](3)[La(NO(3))(6)], 6), 1-methyl-3-octylimidazolium hexanitratolanthanate ([C(8)mim](3)[La(NO(3))(6)], 7), 1-dodecyl-3-methylimidazolium hexanitratolanthanate ([C(12)mim](3)[La(NO(3))(6)], 8), 1-methyl-3-tetradecylimidazolium hexanitratolanthanate ([C(14)mim](3)[La-(NO(3))(6)], 9), 1-hexadecyl-3-methylimid-azolium hexanitratolanthanum ([C(16)dmim](3)[La(NO(3))(6)], 10), and 1-methyl-3-octadecylimidazolium hexanitratolanthanate ([C(18)mim](3)[La(NO(3))(6)], 11) are reported. All new compounds were characterized by (1)H and (13)C NMR, and IR spectroscopy as well as elemental analysis. The crystal structure of compound 1 was determined by using single-crystal X-ray diffraction, giving the following crystallographic information: monoclinic; P2(1)/c; a=15.3170 (3), b=14.2340 (2), c=13.8954(2) Å; β=94.3453(15)°, V=3020.80(9) Å(3), Z=4, ρ=1.764 g cm(-3). The coordination polyhedron around the lanthanum ion is rationalized by six nitrate anions with twelve oxygen atoms. No hydrogen-bonding network or water molecule was found in 1. The thermodynamic stability of the new complexes was investigated by using thermogravimetric analysis (TGA). The water-free hexanitratolanthanate ionic liquids are thermal and moisture stable. Four complexes, namely complexes 8-11, were found to be ionic liquid crystals by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). They all present smectic A liquid-crystalline phase.

Current induced spin-orbit torques driven by the conventional spin Hall effect are widely used to manipulate the magnetization. This approach, however, is nondeterministic and inefficient for the switching of magnets with perpendicular magnetic anisotropy that are demanded by the high-density magnetic storage and memory devices. Here, we demonstrate that this limitation can be overcome by exploiting a magnetic spin Hall effect in noncollinear antiferromagnets, such as Mn3Sn. The magnetic group symmetry of Mn3Sn allows generation of the out-of-plane spin current carrying spin polarization collinear to its direction induced by an in-plane charge current. This spin current drives an out-of-plane anti-damping torque providing the deterministic switching of the perpendicular magnetization of an adjacent Ni/Co multilayer. Due to being odd with respect to time reversal symmetry, the observed magnetic spin Hall effect and the resulting spin-orbit torque can be reversed with reversal of the antiferromagnetic order. Contrary to the conventional spin-orbit torque devices, the demonstrated magnetization switching does not need an external magnetic field and requires much lower current density which is useful for low-power spintronics.

An efficient synthesis of pyrazoles from tosylhydrazones and nitroalkenes was developed. In comparison with the previously reported 1,3-dipolar cycloaddition reaction of diazo compounds with electron-deficient alkenes or alkynes, this methodology proceeded with a sequential Baylis-Hillman/intramolecular cyclization mechanism and a variety of reversed regioselectivity products were prepared in good yields.

An efficient synthesis of 1,3,5-trisubstituted pyrazoles from N-alkylated tosylhydrazones and terminal alkynes was developed. The protocol was applied to a wide range of substrates and demonstrated excellent tolerance to a variety of substituents, including both electron-donating and -withdrawing groups. In comparison with the common approaches for substituted pyrazole syntheses, this methodology proceeded with complete regioselectivity, especially, in the cases that R(2) and R(3) are similar substituents.

The diversity-oriented synthesis of 1,2,4-triazols, 1,3,4-thiadiazols, and 1,3,4-selenadiazoles from N-tosylhydrazones was developed, and the reactions were general for a wide range of substrates, in which NH2CN, KOCN, KSCN, and KSeCN were used as odorless sources. Two different pathways were proposed, and N-tosylhydrazonoyl chlorides were formed in situ in the presence of NCS.

An efficient synthesis of indazoles from readily accessible E/Z mixtures of o‐haloaryl N‐tosylhydrazones has been developed. The thermo‐induced isomerization of N‐tosylhydrazones is discussed. A series of valuable indazole derivatives are prepared in good yields, and the method has been successfully applied to the synthesis of the bioactive compounds, lonidamine, AF‐2785, axitinib, YC‐1 and YD‐3.magnified image

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