Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
J Chem Phys. 2012 Oct 7;137(13):134105. doi: 10.1063/1.4755991.
Born-Oppenheimer molecular dynamics simulations with long-term conservation of the total energy and a computational cost that scales linearly with system size have been obtained simultaneously. Linear scaling with a low pre-factor is achieved using density matrix purification with sparse matrix algebra and a numerical threshold on matrix elements. The extended Lagrangian Born-Oppenheimer molecular dynamics formalism [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] yields microcanonical trajectories with the approximate forces obtained from the linear scaling method that exhibit no systematic drift over hundreds of picoseconds and which are indistinguishable from trajectories computed using exact forces.
同时获得了具有总能量长期守恒和计算成本与系统大小呈线性比例的 Born-Oppenheimer 分子动力学模拟。通过使用稀疏矩阵代数和矩阵元素的数值阈值进行密度矩阵提纯，可以实现具有低预因子的线性比例。扩展的拉格朗日 Born-Oppenheimer 分子动力学形式[AMN Niklasson，Phys Rev Lett 100, 123004（2008）]产生了具有近似力的微正则轨迹，这些力是从线性比例方法获得的，在数百皮秒的时间内没有系统漂移，并且与使用精确力计算的轨迹无法区分。
