Helmholtz-Zentrum Dresden-Rossendorf, Hochfeld Magnetlab Dresden, D-01314 Dresden, Germany.
J Phys Condens Matter. 2013 Feb 13;25(6):065601. doi: 10.1088/0953-8984/25/6/065601. Epub 2013 Jan 11.
The temperature dependence of the spin susceptibilities of S = 1, 3/2, 2, 5/2 and 7/2 Heisenberg antiferromagnetic 1D spins chains with nearest-neighbor coupling was simulated via quantum Monte Carlo calculations, within the reduced temperature range of 0.005 ≤ T* ≤ 100, and fitted to a Padé approximation with deviations between the simulated and fitted data of the same order of magnitude as or smaller than the quantum Monte Carlo simulation error. To demonstrate the practicality of our theoretical findings, we compare these results with the susceptibility of the well known 1D chain compound TMMC ([(CH(3))(4)N[MnCl(3)]], d(5), S = 5/2) and find that different intra-chain spin-exchange parameters result if we consider the data above and below the structural phase transition reported for TMMC at ~126 K. The structural phase transition, which gives rise to an anomaly in the magnetic susceptibility, is independent of the magnetic field up to magnetic fields of 7 T. Additionally, we show that the S = 1 system NiTa(2)O(6) with tri-rutile crystal structure can be very well described as a Heisenberg S = 1 spin chain.
通过量子蒙特卡罗计算模拟了具有最近邻耦合的 S = 1、3/2、2、5/2 和 7/2 海森堡反铁磁 1D 自旋链在 0.005 ≤ T* ≤ 100 的缩减温度范围内的自旋磁化率的温度依赖性，并将其拟合为 Padé 逼近，模拟和拟合数据之间的偏差与量子蒙特卡罗模拟误差的数量级相同或更小。为了展示我们理论发现的实用性，我们将这些结果与知名的 1D 链化合物 TMMC([(CH(3))(4)N[MnCl(3)]]，d(5)，S = 5/2)的磁化率进行了比较，并发现如果我们考虑 TMMC 在 ~126 K 报道的结构相变上下方的数据，则会得到不同的链内自旋交换参数。结构相变导致磁化率出现异常，该异常在磁场高达 7 T 时与磁场无关。此外，我们表明具有三斜金红石晶体结构的 NiTa(2)O(6)S = 1 系统可以很好地描述为海森堡 S = 1 自旋链。
