Large-Scale Molecular Dynamics Simulation for Ground and Excited States Based on Divide-and-Conquer Long-Range Corrected Density-Functional Tight-Binding Method

Abstract

In this study, divide-and-conquer (DC) based density-functional tight-binding (DFTB) and time-dependent density-functional tight-binding (TD-DFTB) methods were developed using long-range correction (LC), which resolved the underestimation of energy gaps between the highest occupied molecular orbital and lowest unoccupied molecular orbital. We implemented the LC term by the entrywise product for the effective utilization of the math kernel library. Test calculations of formaldehyde in explicit water molecules demonstrate the efficiency of the developed method. Furthermore, the DC-TD-LCDFTB method was applied to 2,2′-bipyridine-3,3′-diol (BP­(OH)2), which exhibits excited-state intramolecular proton transfer in polar solvents.

Energy-Based Automatic Determination of Buffer Region in the Divide-and-Conquer Second-Order Møller-Plesset Perturbation Theory

“…[23,24] Yang and coworkers introduced a linear-scaling approach called the divide-andconquer (DC) method. [25,26] The DC method has been applied to the HF or DFT selfconsistent field (SCF), [25,27] density-functional tight-binding, [28][29][30][31] and post-HF (MP2 [32][33][34][35] or CC [36][37][38] ) energy calculations as well as the SCF [39] and MP2 [40] energy gradient calculations. For treating static electron correlation in large-scale systems, the DC method has also been combined with the Hartree-Fock-Bogoliubov method [41] and the thermallyassisted occupation (finite temperature) scheme.…”

Analytic first and second derivatives of the energy in the fragment molecular orbital method combined with molecular mechanics

“…[10,11] One way to accomplish the scaling reduction is provided by fragmentation approaches. [12][13][14][15][16][17][18][19][20][21] Some of them have analytic second derivatives developed. [22][23][24][25][26] Delocalized low frequencies are hard to estimate accurately without anharmonic corrections [27] because the frequencies and corrections may have a similar magnitude.…”

Analytic First and Second Derivatives for the Fragment Molecular Orbital Method Combined with Molecular Mechanics

“…8,9 QM calculations can be accelerated with linear scaling methods 10,11 . One route to accomplish the scaling reduction is provided by fragmentation approaches [12][13][14][15][16][17][18][19][20][21] . Some of them have analytic second derivatives developed [22][23][24][25][26] .…”