Albaugh Alex, Niklasson Anders M N, Head-Gordon Teresa
Theoretical Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States.
Chemical Sciences Division, Lawrence Berkeley National Laboratory, University of California , Berkeley, California 94720, United States.
J Phys Chem Lett. 2017 Apr 20;8(8):1714-1723. doi: 10.1021/acs.jpclett.7b00450. Epub 2017 Apr 4.
We present a new solution for classical polarization that does not require any self-consistent field iterations, the aspect of classical polarization that makes it computationally expensive. The new method builds upon our iEL/SCF Lagrangian scheme that defines a set of auxiliary induced dipoles whose original purpose was to serve as a time-reversible initial guess to the SCF solution of the set of real induced dipoles. In the new iEL/0-SCF approach the auxiliary dipoles now drive the time evolution of the real induced dipoles such that they stay close to the Born-Oppenheimer surface in order to achieve a truly SCF-less method. We show that the iEL/0-SCF exhibits no loss of simulation accuracy when analyzed across bulk water, low to high concentration salt solutions, and small solutes to large proteins in water. In addition, iEL/0-SCF offers significant computational savings over more expensive SCF calculations based on traditional 1 fs time step integration using symplectic integrators and is as fast as reversible reference system propagator algorithms with an outer 2 fs time step.
我们提出了一种针对经典极化的新解决方案，该方案无需任何自洽场迭代，而经典极化的这一方面使其计算成本高昂。新方法基于我们的iEL/SCF拉格朗日方案构建，该方案定义了一组辅助感应偶极子，其最初目的是作为真实感应偶极子集的自洽场解的时间可逆初始猜测。在新的iEL/0-SCF方法中，辅助偶极子现在驱动真实感应偶极子的时间演化，以使它们保持接近玻恩-奥本海默表面，从而实现一种真正无需自洽场的方法。我们表明，在分析 bulk water、低至高浓度盐溶液以及水中从小溶质到大蛋白质的情况时，iEL/0-SCF没有表现出模拟精度的损失。此外，与基于使用辛积分器的传统1 fs时间步长积分的更昂贵的自洽场计算相比，iEL/0-SCF在计算上有显著节省，并且与具有外部2 fs时间步长的可逆参考系统传播子算法一样快。
