A first principles based polarizable O(N) interatomic force field for bulk silica

Kermode, James R.; Cereda, S.; Tangney, Paul; Vita, Alessandro De

doi:10.1063/1.3475565

Cited by 28 publications

(22 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…15 An application to water molecules has also been attempted. 16 The approach has since been reformulated-first, to utilize spline-based potentials in fitting, 14,16 then to introduce a system of virtual springs connecting selected atoms, whose stiffnesses are optimized instead of optimizing the potential parameters.…”

Section: A the Original Learn-on-the-fly Methodsmentioning

confidence: 99%

Hybrid quantum-classical approach for atomistic simulation of metallic systems

Dziedzic

Bobrowski

2011

Phys. Rev. B

View full text Add to dashboard Cite

The learn-on-the-fly (LOTF) method [G. Csànyi et al., Phys. Rev. Lett. 93, 175503 (2004)] serves to seamlessly embed quantum-mechanical computations within a molecular-dynamics framework by continual local retuning of the potential's parameters so that it reproduces the quantum-mechanical forces. In its current formulation, it is suitable for systems where the interaction is short-ranged, such as covalently bonded semiconductors. We propose a substantial extension of the LOTF scheme to metallic systems, where the interaction range is longer and the many-body nature of the potential prevents a straightforward application of the original LOTF technique. We propose to realize the force optimization stage in a divide-and-conquer fashion and give detailed analysis of the difficulties encountered and the means to overcome them. We show how the technique, which we have termed divide and conquer learn-on-the-fly, can be parallelized to utilize several tens of processors. Finally, we present the results of an application of the proposed scheme (utilizing tight binding for the quantum-mechanical part) to nanoindentation and nanoscratching of single-crystal Cu.

show abstract

Section: A the Original Learn-on-the-fly Methodsmentioning

confidence: 99%

Hybrid quantum-classical approach for atomistic simulation of metallic systems

Dziedzic

Bobrowski

2011

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…[4][5][6][7][8] Despite continuous advances, ab initio methods cannot yet tackle the study of various material properties due to length and time scale restrictions. Classical effective potentials greatly increase the accessible system sizes and times; the quality of such simulations, however, depends crucially on the interaction models used.…”

Section: Introductionmentioning

confidence: 99%

Ab initio based polarizable force field generation and application to liquid silica and magnesia

Beck

Brommer²,

Roth

et al. 2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

We extend the program potfit, which generates effective atomic interaction potentials from ab initio data, to electrostatic interactions and induced dipoles. The potential parametrization algorithm uses the Wolf direct, pairwise summation method with spherical truncation. The polarizability of oxygen atoms is modeled with the Tangney-Scandolo interatomic force field approach. Due to the Wolf summation, the computational effort in simulation scales linearly in the number of particles, despite the presence of electrostatic interactions. Thus, this model allows to perform large-scale molecular dynamics simulations of metal oxides with realistic potentials. Details of the implementation are given, and the generation of potentials for SiO(2) and MgO is demonstrated. The approach is validated by simulations of microstructural, thermodynamic, and vibrational properties of liquid silica and magnesia.

show abstract

“…As before, we find that using the average Mulliken charges of a reference QM calculation for the EE leads to slightly more accurate forces. While the MM forces can be systematically improved (e.g, by using a different classical potential 10 ), the large force errors near the boundary of the QM region are a general consequence of the truncated QM calculation. One can imagine finding the best possible shortrange potential that properly links the QM and MM regions, as reported above for the conv-QM/MM geometry optimizations.…”

Section: Finite Temperature Qm/mm MD Simulations Of Crack Propagamentioning

confidence: 99%

“…The bulk quartz sample consists of a cubic quartz cell containing about 2600 atoms, where we initially slightly randomized the atomic positions and then thermalized the system in the NVT ensemble for about 100 fs at a temperature of 1000 K. To do this, we used a short-ranged version of the polarizable potential for silica first developed by Tangney and Scandolo. 10,42 The amorphous slab contains about 1400 atoms and was obtained following the procedure described in Ref. 43.…”

Section: Silica Model Systemsmentioning

confidence: 99%

Accuracy of buffered-force QM/MM simulations of silica

Peguiron

Ciacchi

Vita

et al. 2015

The Journal of Chemical Physics

View full text Add to dashboard Cite

We report comparisons between energy-based quantum mechanics/molecular mechanics (QM/MM) and buffered force-based QM/MM simulations in silica. Local quantities-such as density of states, charges, forces, and geometries-calculated with both QM/MM approaches are compared to the results of full QM simulations. We find the length scale over which forces computed using a finite QM region converge to reference values obtained in full quantum-mechanical calculations is ∼10 Å rather than the ∼5 Å previously reported for covalent materials such as silicon. Electrostatic embedding of the QM region in the surrounding classical point charges gives only a minor contribution to the force convergence. While the energy-based approach provides accurate results in geometry optimizations of point defects, we find that the removal of large force errors at the QM/MM boundary provided by the buffered force-based scheme is necessary for accurate constrained geometry optimizations where Si-O bonds are elongated and for finite-temperature molecular dynamics simulations of crack propagation. Moreover, the buffered approach allows for more flexibility, since special-purpose QM/MM coupling terms that link QM and MM atoms are not required and the region that is treated at the QM level can be adaptively redefined during the course of a dynamical simulation. C 2015 AIP Publishing LLC. [http://dx

show abstract

A first principles based polarizable O(N) interatomic force field for bulk silica

Cited by 28 publications

References 48 publications

Hybrid quantum-classical approach for atomistic simulation of metallic systems

Hybrid quantum-classical approach for atomistic simulation of metallic systems

Ab initio based polarizable force field generation and application to liquid silica and magnesia

Accuracy of buffered-force QM/MM simulations of silica

Contact Info

Product

Resources

About