Toward DMC Accuracy Across Chemical Space with Scalable Δ-QML

Author(s)
Bing Huang, O. Anatole von Lilienfeld, Jaron T. Krogel, Anouar Benali
Abstract

In the past decade, quantum diffusion Monte Carlo (DMC) has been demonstrated to successfully predict the energetics and properties of a wide range of molecules and solids by numerically solving the electronic many-body Schrödinger equation. With O(N3) scaling with the number of electrons N, DMC has the potential to be a reference method for larger systems that are not accessible to more traditional methods such as CCSD(T). Assessing the accuracy of DMC for smaller molecules becomes the stepping stone in making the method a reference for larger systems. We show that when coupled with quantum machine learning (QML)-based surrogate methods, the computational burden can be alleviated such that quantum Monte Carlo (QMC) shows clear potential to undergird the formation of high-quality descriptions across chemical space. We discuss three crucial approximations necessary to accomplish this: the fixed-node approximation, universal and accurate references for chemical bond dissociation energies, and scalable minimal amons-set-based QML (AQML) models. Numerical evidence presented includes converged DMC results for over 1000 small organic molecules with up to five heavy atoms used as amons and 50 medium-sized organic molecules with nine heavy atoms to validate the AQML predictions. Numerical evidence collected for Δ-AQML models suggests that already modestly sized QMC training data sets of amons suffice to predict total energies with near chemical accuracy throughout chemical space.

Organisation(s)
Computational Materials Physics
External organisation(s)
University of Toronto, Technische Universität Berlin, Vector Institute for Artificial Intelligence, Oak Ridge National Laboratory , Argonne National Laboratory
Journal
Journal of Chemical Theory and Computation
Volume
19
Pages
1711–1721
No. of pages
11
ISSN
1549-9618
DOI
https://doi.org/10.1021/acs.jctc.2c01058
Publication date
03-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics, 103043 Computational physics, 104022 Theoretical chemistry
ASJC Scopus subject areas
Computer Science Applications, Physical and Theoretical Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/d519578e-c936-4a68-9130-8462a36b384f