# Accurate molecular dynamics and nuclear quantum effects at low cost by multiple steps in real and imaginary time: Using density functional theory to accelerate wavefunction methods.

@article{Kapil2016AccurateMD, title={Accurate molecular dynamics and nuclear quantum effects at low cost by multiple steps in real and imaginary time: Using density functional theory to accelerate wavefunction methods.}, author={Venkat Kapil and Joost VandeVondele and M. Ceriotti}, journal={The Journal of chemical physics}, year={2016}, volume={144 5}, pages={ 054111 } }

The development and implementation of increasingly accurate methods for electronic structure calculations mean that, for many atomistic simulation problems, treating light nuclei as classical particles is now one of the most serious approximations. Even though recent developments have significantly reduced the overhead for modeling the quantum nature of the nuclei, the cost is still prohibitive when combined with advanced electronic structure methods. Here we present how multiple time step…

## 45 Citations

High order path integrals made easy.

- PhysicsThe Journal of chemical physics
- 2016

This work introduces an inexpensive molecular dynamics scheme that overcomes limitations, thus making it possible to exploit the improved convergence of high-order path integrals without having to sacrifice the stability, convenience, and flexibility of conventional second-order techniques.

Accurate description of nuclear quantum effects with high-order perturbed path integrals (HOPPI).

- PhysicsJournal of chemical theory and computation
- 2020

Perturbed HOPI simulations remain both efficient and accurate down to 20 K and provide a convenient method to estimate the convergence of quantum-mechanical observables.

Ab initio molecular dynamics with nuclear quantum effects at classical cost: Ring polymer contraction for density functional theory.

- ChemistryThe Journal of chemical physics
- 2016

It is shown that the cost of path integral simulations can be dramatically reduced by extending the ring polymer contraction approach to ab initio molecular dynamics simulations, and this development thus offers a route to routinely include nuclear quantum effects in abinitio Molecular dynamics simulations at negligible computational cost.

Affordable Ab Initio Path Integral for Thermodynamic Properties via Molecular Dynamics Simulations Using Semiempirical Reference Potential

- Chemistry
- 2021

Path integral molecular dynamics (PIMD) is becoming a routinely applied method for the incorporation of the nuclear quantum effect in computer simulations. However,
direct PIMD simulations at an ab…

Using a monomer potential energy surface to perform approximate path integral molecular dynamics simulation of ab initio water at near-zero added cost.

- PhysicsPhysical chemistry chemical physics : PCCP
- 2018

A method whereby PIMD can be incorporated into a DFT simulation with little extra cost and little loss in accuracy is introduced, based on the many body expansion of the energy and has the benefit of including a monomer level correction to the DFT energy.

Affordable Ab Initio Path Integral for Thermodynamic Properties via Molecular Dynamics Simulations Using Semiempirical Reference Potential.

- ChemistryThe journal of physical chemistry. A
- 2021

It is shown in this work that the computational expense for the intramolecular proton transfer between the two nitrogen atoms can be remarkably reduced by implementing the idea of reference-potential methods.

Approximate Quantum Dynamics using Ab Initio Classical Separable Potentials: Spectroscopic Applications.

- ChemistryJournal of chemical theory and computation
- 2017

The ab initio classical separable potentials (AICSP) method is proposed as the basis for approximate algorithms of this type and scales very favorably with the number of vibrational modes and should be applicable for very large molecules, e.g., peptides.

Nuclear quantum effects enter the mainstream

- Physics
- 2018

Recent developments are reported on that enable modelling of quantum nuclei at a computational cost comparable with that of a classical simulation, leading to new insights into phenomena that are relevant to different areas of science.

The effect of molecular dynamics sampling on the calculated observable gas-phase structures.

- Physics, ChemistryPhysical chemistry chemical physics : PCCP
- 2016

The quantum GLE thermostat and a posteriori correction to the canonical GLE and NH thermostatted trajectories capture most vibrational quantum effects and closely reproduce computationally expensive PIMD and experimental radial distribution functions.

On the importance of anharmonicities and nuclear quantum effects in modelling the structural properties and thermal expansion of MOF-5.

- PhysicsThe Journal of chemical physics
- 2019

The influence of anharmonicities and nuclear quantum effects (NQEs) in modelling the structural properties and thermal expansion of the empty MOF-5 metal-organic framework is investigated and a sufficiently accurate description of the potential energy surface (PES) is prerequisite when modelling NQEs.

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