Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Box 516, SE-75120, Uppsala, Sweden.
J Chem Phys. 2013 Dec 7;139(21):214102. doi: 10.1063/1.4834015.
We present an efficient general approach to first principles molecular dynamics simulations based on extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] in the limit of vanishing self-consistent field optimization. The reduction of the optimization requirement reduces the computational cost to a minimum, but without causing any significant loss of accuracy or long-term energy drift. The optimization-free first principles molecular dynamics requires only one single diagonalization per time step, but is still able to provide trajectories at the same level of accuracy as "exact," fully converged, Born-Oppenheimer molecular dynamics simulations. The optimization-free limit of extended Lagrangian Born-Oppenheimer molecular dynamics therefore represents an ideal starting point for robust and efficient first principles quantum mechanical molecular dynamics simulations.
我们提出了一种基于扩展拉格朗日 Born-Oppenheimer 分子动力学（A. M. N. Niklasson，Phys. Rev. Lett. 100, 123004 (2008)）的有效全量子力学分子动力学模拟的通用方法，该方法在自洽场优化趋于零时有效。优化要求的降低将计算成本降至最低，但不会导致精度或长期能量漂移的显著损失。无优化的全量子力学分子动力学仅需要每个时间步进行一次对角化，但仍然能够提供与“精确”、完全收敛的 Born-Oppenheimer 分子动力学模拟相同水平的轨迹。因此，扩展拉格朗日 Born-Oppenheimer 分子动力学的无优化极限是稳健和高效全量子力学分子动力学模拟的理想起点。
