TY - JOUR

T1 - Analytical nuclear gradients for the range-separated many-body DiSpersion model of noncovalent interactions

AU - Blood-Forsythe, Martin A.

AU - Markovich, Thomas

AU - DiStasio, Robert A.

AU - Car, Roberto

AU - Aspuru-Guzik, Alán

N1 - Funding Information:
We thank Alexandre Tkatchenko and Alberto Ambrosetti for useful discussions and for providing source code for the FHI-aims implementation of MBD. This research used resources of the Odyssey cluster supported by the FAS Division of Science, Research Computing Group at Harvard University, the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, the Texas Advanced Computing Center (TACC) at The University of Texas at Austin, the Extreme Science and Engineering Discovery Environment (XSEDE),143 which is supported by National Science Foundation Grant No. ACI-1053575, and the Argonne Leadership Computing Facility at Argonne National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under contract DE-AC02-06CH11357. M. A. B.-F. acknowledges support from the DOE Office of Science Graduate Fellowship Program, made possible in part by the American Recovery and Reinvestment Act of 2009, administered by ORISE-ORAU under Contract No. DE-AC05-06OR23100. T. M. acknowledges support from the National Science Foundation (NSF) Graduate Research Fellowship Program. R. A. D. and R. C. acknowledge support from the Scientific Discovery through Advanced Computing (SciDAC) program through the Department of Energy under Grant No. DE-SC0008626. A. A.-G. acknowledges support from the STC Center for Integrated Quantum Materials, NSF Grant No. DMR-1231319. All opinions expressed in this paper are the authors'' and do not necessarily reflect the policies and views of DOE, ORAU, ORISE, or NSF.

PY - 2016/3/1

Y1 - 2016/3/1

N2 - An accurate treatment of the long-range electron correlation energy, including van der Waals (vdW) or DiSpersion interactions, is essential for describing the structure, dynamics, and function of a wide variety of systems. Among the most accurate models for including DiSpersion into density functional theory (DFT) is the range-separated many-body DiSpersion (MBD) method [A. Ambrosetti et al., J. Chem. Phys., 2014, 140, 18A508], in which the correlation energy is modeled at short-range by a semi-local density functional and at long-range by a model system of coupled quantum harmonic oscillators. In this work, we develop analytical gradients of the MBD energy with respect to nuclear coordinates, including all implicit coordinate dependencies arising from the partitioning of the charge density into Hirshfeld effective volumes. To demonstrate the efficiency and accuracy of these MBD gradients for geometry optimizations of systems with intermolecular and intramolecular interactions, we optimized conformers of the benzene dimer and isolated small peptides with aromatic side-chains. We find excellent agreement with the wavefunction theory reference geometries of these systems (at a fraction of the computational cost) and find that MBD consistently outperforms the popular TS and D3(BJ) DiSpersion corrections. To demonstrate the performance of the MBD model on a larger system with supramolecular interactions, we optimized the C60@C60H28 buckyball catcher host-guest complex. In our analysis, we also find that neglecting the implicit nuclear coordinate dependence arising from the charge density partitioning, as has been done in prior numerical treatments, leads to an unacceptable error in the MBD forces, with relative errors of ∼20% (on average) that can extend well beyond 100%.

AB - An accurate treatment of the long-range electron correlation energy, including van der Waals (vdW) or DiSpersion interactions, is essential for describing the structure, dynamics, and function of a wide variety of systems. Among the most accurate models for including DiSpersion into density functional theory (DFT) is the range-separated many-body DiSpersion (MBD) method [A. Ambrosetti et al., J. Chem. Phys., 2014, 140, 18A508], in which the correlation energy is modeled at short-range by a semi-local density functional and at long-range by a model system of coupled quantum harmonic oscillators. In this work, we develop analytical gradients of the MBD energy with respect to nuclear coordinates, including all implicit coordinate dependencies arising from the partitioning of the charge density into Hirshfeld effective volumes. To demonstrate the efficiency and accuracy of these MBD gradients for geometry optimizations of systems with intermolecular and intramolecular interactions, we optimized conformers of the benzene dimer and isolated small peptides with aromatic side-chains. We find excellent agreement with the wavefunction theory reference geometries of these systems (at a fraction of the computational cost) and find that MBD consistently outperforms the popular TS and D3(BJ) DiSpersion corrections. To demonstrate the performance of the MBD model on a larger system with supramolecular interactions, we optimized the C60@C60H28 buckyball catcher host-guest complex. In our analysis, we also find that neglecting the implicit nuclear coordinate dependence arising from the charge density partitioning, as has been done in prior numerical treatments, leads to an unacceptable error in the MBD forces, with relative errors of ∼20% (on average) that can extend well beyond 100%.

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U2 - 10.1039/c5sc03234b

DO - 10.1039/c5sc03234b

M3 - Article

C2 - 29899903

AN - SCOPUS:84959420351

VL - 7

SP - 1712

EP - 1728

JO - Chemical Science

JF - Chemical Science

SN - 2041-6520

IS - 3

ER -