Open-Source Fermionic Neural Networks with Ionic Charge Initialization
Shai Pranesh, Shang Zhu, Venkat Viswanathan, Bharath Ramsundar
TL;DR
This work tackles accurate electronic structure calculations for molecules and ions using variational Monte Carlo with neural-network wavefunctions by integrating the FermiNet into the open-source DeepChem platform. It introduces a Mulliken-based ionic charge initialization to correctly assign electron counts in ions, and employs HF baselines to stabilize and accelerate training. Empirical results on H2 and LiH+ show FermiNet energies closely tracking CCSD benchmarks and outperforming HF, illustrating practical gains in accuracy and convergence. The open-source integration aims to enable rapid, differentiable-physics–driven experimentation in quantum chemistry, with future plans to incorporate performance optimizations and physics priors from related models such as PauliNet.
Abstract
Finding accurate solutions to the electronic Schrödinger equation plays an important role in discovering important molecular and material energies and characteristics. Consequently, solving systems with large numbers of electrons has become increasingly important. Variational Monte Carlo (VMC) methods, especially those approximated through deep neural networks, are promising in this regard. In this paper, we aim to integrate one such model called the FermiNet, a post-Hartree-Fock (HF) Deep Neural Network (DNN) model, into a standard and widely used open source library, DeepChem. We also propose novel initialization techniques to overcome the difficulties associated with the assignment of excess or lack of electrons for ions.
