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تسجيل مستخدم جديدItinerant G-type antiferromagnetic order in SrCr$_2$As$_2$
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Neutron diffraction and magnetic susceptibility studies of a polycrystalline SrCr$_2$As$_2$ sample reveal that this compound is an itinerant G-type antiferromagnet below the N${rm acute{e}}$el temperature $T_{textrm N}$ = 590(5) K with the Cr magnetic moments aligned along the tetragonal $c$ axis. The system remains tetragonal to the lowest measured temperature ($sim$12 K). The lattice parameter ratio $c/a$ and the magnetic moment saturate at about the same temperature below $sim$ 200 K, indicating a possible magnetoelastic coupling. The ordered moment, $mu=1.9(1)~mu_{rm B}$/Cr, measured at $T = 12$ K, is significantly reduced compared to its localized value ($4~mu_{rm B}$/Cr) due to the itinerant character brought about by the hybridization between the Cr $3d$ and As $4p$ orbitals.
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