论文标题
$ s = 1 $扶手椅链中的自旋相关性的NMR研究Ni $ _2 $ nbbo $ _6 $
NMR study of the spin correlations in the $S=1$ armchair chain Ni$_2$NbBO$_6$
论文作者
论文摘要
我们报告了对结构自旋链化合物Ni $ _2 $ nbbo $ _6 $的核磁共振（NMR）研究，并具有复杂的磁耦合。通过交错的内部超精细场导致的线分裂来监测抗铁磁过渡。我们的NMR光谱分析支持了第一原则密度功能理论（DFT）提出的磁耦合构型。对于自旋动力学，从旋转局限性放松数据中观察到了$ t \ sim35 $ k的突出峰值（$ t_n \ sim20 $ k），$μ_0H= 10 $ t）。与DC敏感性相比，此行为表明与$ \ sim3 $ MEV的典型能量量表具有抗磁磁耦合。因此，ni $ _2 $ nbbo $ _6 $化合物可以被视为沿着晶体$ b $轴的强烈的铁磁耦合扶手椅旋转链。这些事实对该化合物的理论模型施加了强烈的限制。
We report our nuclear magnetic resonance (NMR) study on the structurally spin chain compound Ni$_2$NbBO$_6$ with complex magnetic coupling. The antiferromagnetic transition is monitored by the line splitting resulting from the staggered internal hyperfine field. The magnetic coupling configuration proposed by the first-principle density functional theory (DFT) is supported by our NMR spectral analysis. For the spin dynamics, a prominent peak at $T\sim35$ K well above the Néel temperature ($T_N\sim20$ K at $μ_0H=10$ T) is observed from the spin-lattice relaxation data. As compared with the dc-susceptibility, this behavior indicates a antiferromagnetic coupling with the typical energy scale of $\sim3$ meV. Thus, the Ni$_2$NbBO$_6$ compound can be viewed as strongly ferromagnetically coupled armchair spin chains along the crystalline $b$-axis. These facts place strong constraints to the theoretical model for this compound.
