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تسجيل مستخدم جديدMagnetic anisotropy in HoIr$_2$Si$_2$ ($I4/mmm$)
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Single crystals of HoIr$_2$Si$_2$ with the body-centered ThCr$_2$Si$_2$-type structure ($I4/mmm$) were grown by Bridgman method from indium flux. Single crystal structure determination yielded a Si-z position of 0.378(1) in the structure. We excluded the presence of the high temperature phase with the primitive CaBe$_2$Ge$_2$-type structure ($P 4/n m m$) by powder X-ray diffraction. Magnetic measurements on the single crystals yield a Neel temperature of $T_{rm N}=22,rm K$. In the inverse magnetic susceptibility a strong anisotropy with Weiss temperatures $Theta_{W}^{001}=26,rm K$ and $Theta_{W}^{100}=-26,rm K$ occurs above $T_{rm N}$. The effective magnetic moment $mu_{rm eff}^{001}=10.64mu_{B}$ and $mu_{rm eff}^{100}=10.53mu_{B}$ is close to the expected value for a free Ho$^{3+}$ ion, $mu_{rm eff}^{calc}=10.6mu_{B}$. The field dependent magnetization shows a step-like behaviour due to crystalline electric field effects.
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