Triphenyl{(E)-4-[4-(phenyldiazenyl)phenyl]-4H-1,2,4-triazol-1-yl}boron

In the title compound, C32H26BN5 or [(C14H11N5)B(C6H5)3], the B atom is approximately tetra­hedrally coordinated. The diazo unit is in a trans conformation, which is generally more stable than a cis one for aromatic azo compounds. The crystal structure features very weak C—H⋯π inter­actions. The dihedral angles between the central benzene ring and the terminal rings in the heterocycle are 62.64, 73.54 and 61.60°

Incommensurate-commensurate transitions in the monoaxial chiral helimagnet driven by the magnetic field

Under the terms of the Creative Commons Attribution license.-- et al.The zero-temperature phase diagram of the monoaxial chiral helimagnet in the magnetic-field plane formed by the components parallel and perpendicular to the helical axis is thoroughly analyzed. The nature of the transition to the commensurate state depends on the angle between the field and the helical axis. For field directions close to the directions parallel or perpendicular to the helical axis the transition is continuous, while for intermediate angles the transition is discontinuous and the incommensurate and commensurate states coexist on the transition line. The continuous and discontinuous transition lines are separated by two tricritical points with specific singular behavior. The location of the continuous and discontinuous lines and of the tricritical points depend strongly on the easy-plane anisotropy, the effect of which is analyzed. For high anisotropy the conical approximation locates the transition line very accurately, although it does not predict the continuous transitions and the tricritical behavior. It is shown that for high anisotropy, as in CrNb3S6, the form of the transition line is universal, that is, independent of the sample, and obeys a simple equation. The position of the tricritical points, which is not universal, is theoretically estimated for a sample of CrNb3S6.J.C. and V.L. acknowledge Grant No. MAT2015-68200-C2-2-P from the Spanish Ministry of Economy and Competitiveness. The work of A. S. Ovchinnikov was supported by the Government of the Russian Federation Program (02.A03.21.0006) and by the Ministry of Education and Science of the Russian Federation (Project Nos. 1437 and 2725).Peer Reviewe

Dichlorido[1-(8-quinolylimino­meth­yl)-2-naphtholato]iron(III)

The FeIII ion in the title complex, [FeCl2(C20H13N2O)], has a distorted square-pyramidal coordination formed by one O atom and two N atoms from a tridentate 1-(8-quinolylimino­meth­yl)-2-naphtholate ligand and two Cl atoms. In the crystal structure, mol­ecules form a column structure along the a axis through π–π stacking inter­actions, with centroid–centroid distances of 3.657 (1) and 3.818 (2) Å. Weak C—H⋯Cl inter­actions are observed between the columns

Incommensurate--commensurate transitions in the mono-axial chiral helimagnet driven by the magnetic field

The zero temperature phase diagram of the mono-axial chiral helimagnet in the magnetic field plane formed by the components parallel and perpendicular to the helical axis is thoroughly analyzed. The nature of the transition to the commensurate state depends on the angle between the field and the helical axis. For field directions close to the directions parallel or perpendicular to the helical axis the transition is continuous, while for intermediate angles the transition is discontinuous and the incommensurate and commensurate states coexist on the transition line. The continuous and discontinuous transition lines are separated by two tricritical points with specific singular behaviour. The location of the continuous and discontinuous lines and of the tricritical points depend strongly on the easy-plane anisotropy, the effect of which is analyzed. For large anisotropy the conical approximation locates the transition line very accurately, although it does not predict the continuous transitions nor the tricitical behaviour. It is shown that for large anisotropy, as in CrNb3S6, the form of the transition line is universal, that is, independent of the sample, and obeys a simple equation. The position of the tricritical points, which is not universal, is theoretically estimated for a sample of CrNb3S6Comment: 10 pages, 9 figure

Chiral Soliton Lattice Formation in Monoaxial Helimagnet Yb(Ni1−x_{1-x}Cux_x)3_3Al9_9

Helical magnetic structures and its responses to external magnetic fields in Yb(Ni$_x$Cu$_{1-x}$)$_3$Al$_9$, with a chiral crystal structure of the space group $R32$, have been investigated by resonant X-ray diffraction. It is shown that the crystal chirality is reflected to the helicity of the magnetic structure by a one to one relationship, indicating that there exists an antisymmetric exchange interaction mediated via the conduction electrons. When a magnetic field is applied perpendicular to the helical axis ($c$ axis), the second harmonic peak of $(0, 0, 2q)$ develops with increasing the field. The third harmonic peak of $(0, 0, 3q)$ has also been observed for the $x$=0.06 sample. This result provides a strong evidence for the formation of a chiral magnetic soliton lattice state, a periodic array of the chiral twist of spins, which has been suggested by the characteristic magnetization curve. The helical ordering of magnetic octupole moments, accompanying with the magnetic dipole order, has also been detected.Comment: 13 pages, 18 figures, accepted for publication in J. Phys. Soc. Jp

HBT signature for clustered substructures probing primordial inhomogeneity in hot and dense QCD matter

We propose a novel approach to probe primordial inhomogeneity in hot and dense matter which could be realized in non-central heavy-ion collisions. Although the Hanbury Brown and Twiss (HBT) interferometry is commonly used to infer the system size, the cluster size should be detected if substructures emerge in space. We demonstrate that a signal peak in the HBT two-particle correlation stands at the relative momentum corresponding to the spatial scale of pseudo one-dimensional modulation. We assess detectability using the data prepared by an event generator (AMPT model) with clustering implemented in the particle distribution.Comment: 5 pages, 4 figure

Current-induced shuttlecock-like movement of non-axisymmetric chiral skyrmions

Current-induced motion of non-axisymmetric skyrmions within tilted ferromagnetic phases of polar helimagnets with the easy plane anisotropy is studied by micromagnetic simulations. Such non-axisymmetric skyrmions consist of a circular core and a crescent-shaped domain-wall region formed with respect to the tilted surrounding state. Current-driven motion of non-axisymmetric skyrmions exhibits two distinct time regimes: initially the skyrmions rotate towards the current flow direction and subsequently move along the current with the skyrmionic crescent first. According to the Thiele equation, the asymmetric distribution of the topological charge and the dissipative force tensor play an important role for giving the different velocities for the circular and the crescent-shaped constituent parts of the skyrmion what underlies such a shuttlecock-like movement. Moreover, the current-velocity relation depends on the angle of the tilted ferromagnetic phase what makes in particular the transverse velocity of skyrmions sensitive to their field-driven configurational transformation. We also argue the possibility of magnetic racetrack waveguides based on complex interplay of robust asymmetric skyrmions with multiple twisted edge states