Real-World Predictions from Ab Initio Molecular Dynamics Simulations - Multiscale Molecular Methods in Applied Chemistry - page 110

Solvent effect String method van der Waals interaction Wannier orbitals

Water Wavelets

Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
2 Ab Initio Molecular Dynamics Simulations in a Nutshell ................................ 112
2.1 Molecular Dynamics Simulations: Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
2.2 Obtaining the Forces and Integrating
the Equations of Motion . . . ........................................................... 113
2.3 Born-Oppenheimer Molecular Dynamics Simulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
2.4 Car-Parrinello Molecular Dynamics Simulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
2.5 Generalization of the Car-Parrinello and Born-Oppenheimer Molecular Dynamics
Approaches ............................................................................ 117
3 Faster, Larger, and More Accurate: Recent Developments ............................... 121
3.1 Massively Parallel Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
3.2 Basis Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
3.3 New Developments in Accuracy . .................................................... 124
3.4 New Integration Schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
3.5 Enhanced Sampling . .................................................................. 130
3.6 Properties: IR, NMR and EXAFS .................................................... 133
4 Applications in Chemical Engineering . . .................................................. 136
4.1 Wavefunction Analysis . .............................................................. 136
4.2 Properties of the Vapor Phase, Liquids, Mixtures, and Solvent Effects . . .......... 137
4.3 Chemical Reactions ................................................................... 141
4.4 Electrochemistry ...................................................................... 143
5 Summary . . .................................................................................. 147
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Abbreviations

AIMD Ab initio molecular dynamics; molecular dynamics with electronic

structure calculations on the fly

ASPC Always stable predictor-corrector algorithm

BOMD Born-Oppenheimer molecular dynamics; molecular dynamics with

electronic structure calculations on the fly, diagonalization in each step

CPMD Car-Parrinello molecular dynamics; molecular dynamics with elec-

tronic structure calculations on the fly, orthogonalization in each step
otherwise the coefficients of the wavefunction are propagated like the
nuclear positions

CV Collective variables

DFT Density functional theory; static quantum chemical method using

functionals of the electronic density to account for electron correlation

DVR Discrete variable representation

ECP Effective core potential also called pseudopotential

FBR Finite basis representation

FES Free energy surface

FFT Fast Fourier transformation