Kuprov Ilya
Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UK.
J Magn Reson. 2008 Nov;195(1):45-51. doi: 10.1016/j.jmr.2008.08.008. Epub 2008 Aug 27.
We extend the recently proposed state-space restriction (SSR) technique for quantum spin dynamics simulations [Kuprov et al., J. Magn. Reson. 189 (2007) 241-250] to include on-the-fly detection and elimination of unpopulated dimensions from the system density matrix. Further improvements in spin dynamics simulation speed, frequently by several orders of magnitude, are demonstrated. The proposed zero track elimination (ZTE) procedure is computationally inexpensive, reversible, numerically stable and easy to add to any existing simulation code. We demonstrate that it belongs to the same family of Krylov subspace techniques as the well-known Lanczos basis pruning procedure. The combined SSR+ZTE algorithm is recommended for simulations of NMR, EPR and Spin Chemistry experiments on systems containing between 10 and 10(4) coupled spins.
我们将最近提出的用于量子自旋动力学模拟的状态空间限制（SSR）技术[库普罗夫等人，《磁共振杂志》189（2007）241 - 250]进行扩展，以实现对系统密度矩阵中未填充维度的实时检测和消除。结果表明，自旋动力学模拟速度有了进一步提升，通常能提高几个数量级。所提出的零轨迹消除（ZTE）程序计算成本低、可逆、数值稳定且易于添加到任何现有的模拟代码中。我们证明它与著名的兰索斯基矢修剪程序属于同一类克雷洛夫子空间技术。对于包含10到10⁴个耦合自旋的系统的核磁共振（NMR）、电子顺磁共振（EPR）和自旋化学实验模拟，推荐使用SSR + ZTE组合算法。
