2023/08/31 by David Pfau, Simon Axelrod, Halvard Sutterud +2 · 1 voice · 50 citations
Materials Science · Mathematics · Physics and Astronomy · #Advanced Chemical Physics Studies #Algorithm #Artificial intelligence #Artificial neural network #Computation #Computer science #Diagonal #Dipole #Excitation #Excited state #Machine Learning in Materials Science #Mathematics #Observable #Orthogonalization #Physics #Quantum #Quantum mechanics #Spectroscopy and Quantum Chemical Studies #Statistical physics #Work (physics)
paper · pdf · doi:10.1126/science.adn0137
published in Science 385(6711), eadn0137 (American Association for the Advancement of Science)
openalex publication_date 2024/08/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We present an algorithm to estimate the excited states of a quantum system by variational Monte Carlo, which has no free parameters and requires no orthogonalization of the states, instead transforming the problem into that of finding the ground state of an expanded system. Arbitrary observables can be calculated, including off-diagonal expectations, such as the transition dipole moment. The method works particularly well with neural network ansätze, and by combining this method with the FermiNet and Psiformer ansätze, we can accurately recover excitation energies and oscillator strengths on a range of molecules. We achieve accurate vertical excitation energies on benzene-scale molecules, including challenging double excitations. Beyond the examples presented in this work, we expect that this technique will be of interest for atomic, nuclear, and condensed matter physics.