TY - JOUR

T1 - Hybrid particle-field molecular dynamics under constant pressure

AU - Bore, Sigbjørn Løland

AU - Kolli, Hima Bindu

AU - De Nicola, Antonio

AU - Byshkin, Maksym

AU - Kawakatsu, Toshihiro

AU - Milano, Giuseppe

AU - Cascella, Michele

N1 - Funding Information:
The authors acknowledge the support of the Norwegian Research Council through the CoE Hylleraas Centre for Quantum Molecular Sciences (Grant No. 262695) and the Norwegian Supercomputing Program (NOTUR) (Grant No. NN4654K). M.C. acknowledges funding by the Deutsche Forschungsgemein-schaft (DFG) within the project B5 of the TRR 146 (Project No. 233630050). H.B.K. received funding from the European Union Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement HYPERBIO—No. 704491.
Publisher Copyright:
© 2020 Author(s).

PY - 2020/5/14

Y1 - 2020/5/14

N2 - Hybrid particle-field methods are computationally efficient approaches for modeling soft matter systems. So far, applications of these methodologies have been limited to constant volume conditions. Here, we reformulate particle-field interactions to represent systems coupled to constant external pressure. First, we show that the commonly used particle-field energy functional can be modified to model and parameterize the isotropic contributions to the pressure tensor without interfering with the microscopic forces on the particles. Second, we employ a square gradient particle-field interaction term to model non-isotropic contributions to the pressure tensor, such as in surface tension phenomena. This formulation is implemented within the hybrid particle-field molecular dynamics approach and is tested on a series of model systems. Simulations of a homogeneous water box demonstrate that it is possible to parameterize the equation of state to reproduce any target density for a given external pressure. Moreover, the same parameterization is transferable to systems of similar coarse-grained mapping resolution. Finally, we evaluate the feasibility of the proposed approach on coarse-grained models of phospholipids, finding that the term between water and the lipid hydrocarbon tails is alone sufficient to reproduce the experimental area per lipid in constant-pressure simulations and to produce a qualitatively correct lateral pressure profile.

AB - Hybrid particle-field methods are computationally efficient approaches for modeling soft matter systems. So far, applications of these methodologies have been limited to constant volume conditions. Here, we reformulate particle-field interactions to represent systems coupled to constant external pressure. First, we show that the commonly used particle-field energy functional can be modified to model and parameterize the isotropic contributions to the pressure tensor without interfering with the microscopic forces on the particles. Second, we employ a square gradient particle-field interaction term to model non-isotropic contributions to the pressure tensor, such as in surface tension phenomena. This formulation is implemented within the hybrid particle-field molecular dynamics approach and is tested on a series of model systems. Simulations of a homogeneous water box demonstrate that it is possible to parameterize the equation of state to reproduce any target density for a given external pressure. Moreover, the same parameterization is transferable to systems of similar coarse-grained mapping resolution. Finally, we evaluate the feasibility of the proposed approach on coarse-grained models of phospholipids, finding that the term between water and the lipid hydrocarbon tails is alone sufficient to reproduce the experimental area per lipid in constant-pressure simulations and to produce a qualitatively correct lateral pressure profile.

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U2 - 10.1063/5.0007445

DO - 10.1063/5.0007445

M3 - Article

C2 - 32414244

AN - SCOPUS:85084935722

SN - 0021-9606

VL - 152

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

IS - 18

M1 - 0007445

ER -