Anisotropy of the Proton Momentum Distribution in Water

Kapil, Venkat; Cuzzocrea, Alice; Ceriotti, Michele

doi:10.1021/acs.jpcb.8b03896

Cited by 17 publications

(15 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…• open path integrals and momentum distribution estimators (V. Kapil, A. Cuzzocrea, M. Ceriotti) [25]; makes it possible to compute the particle momentum distribution including quantum fluctuations of nuclei;…”

Section: Program Featuresmentioning

confidence: 99%

i-PI 2.0: A universal force engine for advanced molecular simulations

Kapil

Rossi

Maršálek

et al. 2019

Computer Physics Communications

Self Cite

333

247

View full text Add to dashboard Cite

Progress in the atomic-scale modelling of matter over the past decade has been tremendous. This progress has been brought about by improvements in methods for evaluating interatomic forces that work by either solving the electronic structure problem explicitly, or by computing accurate approximations of the solution and by the development of techniques that use the Born-Oppenheimer (BO) forces to move the atoms on the BO potential energy surface. As a consequence of these developments it is now possible to identify stable or metastable states, to sample configurations consistent with the appropriate thermodynamic ensemble, and to estimate the kinetics of reactions and phase transitions. All too often, however, progress is slowed down by the bottleneck associated with implementing new optimization algorithms and/or sampling techniques into the many existing electronic-structure and empirical-potential codes. To address this problem, we are thus releasing a new version of the i-PI software. This piece of software is an easily extensible framework for implementing advanced atomistic simulation techniques using interatomic potentials and forces calculated by an external driver code. While the original version of the code[1] was developed with a focus on path integral molecular dynamics techniques, this second release of i-PI not only includes several new advanced path integral methods, but also offers other classes of algorithms. In other words, i-PI is moving towards becoming a universal force engine that is both modular and tightly coupled to the driver codes that evaluate the potential energy surface and its derivatives.

show abstract

Section: Program Featuresmentioning

confidence: 99%

i-PI 2.0: A universal force engine for advanced molecular simulations

Kapil

Rossi

Maršálek

et al. 2019

Computer Physics Communications

Self Cite

333

247

View full text Add to dashboard Cite

show abstract

“…64 ring-polymer beads were used, which is sufficient to converge the properties of interest even at low temperatures. [30,51] For dynamical properties, thermostatted ring polymer molecular dynamics (TRPMD) [52], which has been shown to predict accurate vibrational dynamics of liquid water [29,53], and partially adiabatic centroid molecular dynamics (PACMD) [54]. A timestep of 0.25 fs was used for TRPMD calculations, and 0.05 fs for PACMD.…”

Section: Computational Detailsmentioning

confidence: 99%

Quantum Dynamics of Water from Møller-Plesset Perturbation Theory via a Neural Network Potential

Lan

Wilkins

Рыбкин

et al. 2021

Preprint

View full text Add to dashboard Cite

We report the static and dynamical properties of liquid water at the level of second-order Møller-Plesset per- perturbation theory (MP2) with classical and quantum nuclear dynamics using a neural network potential. We examined the temperature-dependent radial distribution functions, diffusion, and vibrational dynamics. MP2 theory predicts over-structured liquid water as well as a lower diffusion coefficient at ambient conditions compared to experiments, which may be attributed to the incomplete basis set. A better agreement with experimental structural properties and the diffusion constant are observed at an elevated temperature of 340 K from our simulations. Although the high-level electronic structure calculations are expensive, training a neural network potential requires only a few thousand frames. The approach is promising as it involves modest human effort and is straightforwardly extensible to other simple liquids.

show abstract

“…The second method reduces the frequency at which the long-ranged interactions are computed by the use of a longer time step for the integration. The two methods can also be used together to achieve substantial computational savings 28,55 and can be seamlessly combined with our high order constant pressure scheme.…”

Section: Accelerated Simulation Schemementioning

confidence: 99%

Modeling the Structural and Thermal Properties of Loaded Metal–Organic Frameworks. An Interplay of Quantum and Anharmonic Fluctuations

Kapil

Wieme

Vandenbrande

et al. 2019

J. Chem. Theory Comput.

Self Cite

View full text Add to dashboard Cite

Metal-organic frameworks show both fundamental interest and great promise for applications in adsorption-based technologies, such as the separation and storage of gases. The flexibility and complexity of the molecular scaffold poses a considerable challenge to atomistic modeling, especially when also considering the presence of guest molecules. We investigate the role played by quantum and anharmonic fluctuations in the archetypical case of MOF-5, comparing the material at various levels of methane loading. Accurate path integral simulations of such effects are made affordable by the introduction of an accelerated simulation scheme and the use of an optimized force 1 arXiv:1901.03770v1 [cond-mat.mtrl-sci] 11 Jan 2019field based on first-principles reference calculations. We find that the level of statistical treatment that is required for predictive modeling depends significantly on the property of interest. The thermal properties of the lattice are generally well described by a quantum harmonic treatment, with the adsorbate behaving in a classical but strongly anharmonic manner. The heat capacity of the loaded framework -which plays an important role in the characterization of the framework and in determining its stability to thermal fluctuations during adsorption/desorption cycles -requires, however, a full quantum and anharmonic treatment, either by path integral methods or by a simple but approximate scheme. We also present molecular-level insight into the nanoscopic interactions contributing to the material's properties and suggest design principles to optimize them.

show abstract

Anisotropy of the Proton Momentum Distribution in Water

Cited by 17 publications

References 44 publications

i-PI 2.0: A universal force engine for advanced molecular simulations

i-PI 2.0: A universal force engine for advanced molecular simulations

Quantum Dynamics of Water from Møller-Plesset Perturbation Theory via a Neural Network Potential

Modeling the Structural and Thermal Properties of Loaded Metal–Organic Frameworks. An Interplay of Quantum and Anharmonic Fluctuations

Contact Info

Product

Resources

About