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CoSe$_2$O$_5$ has a crystal structure consisting of zig-zag chains of edge shared CoO$_6$ octahedra running along the c axis, with the chains separated by Se$_2$O$_5^{2-}$ units. Magnetic susceptibility measurements indicate a transition at 8.5 K to an ordered state. We investigate here the nature of this magnetic ordering using magnetization and specific heat measurements in addition to powder neuttron diffraction. A transition to long-range antiferromagnetic order is found below $T_N$ = 8.5 K as identified by magnetic susceptibility measurements and magnetic Bragg reflections, with a propagation vector $mathbf{k}$ = 0. The magnetic structure shows that the moments align perpendicular to the c-axis, but with the spins canting with respect to the a axis by, alternately, $+8^circ$ and $-8^circ$. Interestingly, the low-field magnetic susceptibility does not show the anticipated cusp-like behavior expected for a well-ordered antiferromagnet. When the susceptibility is acquired under field-cooling conditions under a 10 kOe field, the the usual downturn expected for antiferromagnetic ordering is obtained. Heat capacity measurements at low temperatures indicate the presence of gapped behavior with a gap of 6.5 K.
A study by specific heat of a polycrystalline sample of the low-dimensional magnetic system Y$_2$BaCuO$_5$ is presented. Magnetic fields up to 14 T are applied and permit to extract the ($T$,$H$) phase diagram. Below $mu_0H^*simeq2$ T, the Neel tempe
Magnetization measurements on single-crystal cubic SrCuTe$_2$O$_6$ with an applied magnetic field of along three inequivalent high symmetry directions $[100]$, $[110]$, and $[111]$ reveal weak magnetic anisotropy. The fits of the magnetic susceptibil
Experimental results on magnetic resonance (ESR) and magnetic susceptibility are given for single crystalline (VO)$_2$P$_2$O$_{7}$. The crystal growth procedure is briefly discussed. The susceptibility is interpreted numerically using a model with al
Magnetic frustration in three dimensions (3D) manifests itself in the spin-$frac12$ insulator Li$_2$CuW$_2$O$_8$. Density-functional band-structure calculations reveal a peculiar spin lattice built of triangular planes with frustrated interplane coup
Amorphous oxide thin films play a fundamental role in state-of-the art interferometry experiments, such as gravitational wave detectors where these films compose the high reflectance mirrors of end and input masses. The sensitivity of these detectors