Quantum Proton Effects from Density Matrix Renormalization Group Calculations.

  title={Quantum Proton Effects from Density Matrix Renormalization Group Calculations.},
  author={Robert Feldmann and Andrea Muolo and Alberto Baiardi and Markus Reiher},
  journal={Journal of chemical theory and computation},
We recently introduced [J. Chem. Phys. 2020, 152, 204103] the nuclear-electronic all-particle density matrix renormalization group (NEAP-DMRG) method to solve the molecular Schrödinger equation, based on a stochastically optimized orbital basis, without invoking the Born-Oppenheimer approximation. In this work, we combine the DMRG method with the nuclear-electronic Hartree-Fock (NEHF-DMRG) approach, treating nuclei and electrons on the same footing. Inter- and intraspecies correlations are… 

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