Pre-Born-Oppenheimer Molecular Structure Theory

Abstract

In pre-Born-Oppenheimer (pre-BO) theory a molecule is considered as a quantum system as a whole, including the electrons and the atomic nuclei on the same footing. This approach is fundamentally different from the traditional quantum chemistry treatment, which relies on the separation of the motion of the electrons and the atomic nuclei. A fully quantum mechanical treatment of molecules has a great promise for future developments and applications. Its most accurate versions may contribute to the definition of new schemes for metrology and testing fundamental physical theories; its approximate versions can provide an efficient theoretical description for molecule-positron interactions and, in general, it would circumvent the tedious computation and fitting of potential energy surfaces and non-adiabatic coupling vectors. To achieve these goals, the review points out important technical and fundamental open questions. Most interestingly, the reconciliation of pre-BO theory with the classical chemistry knowledge touches upon fundamental problems related to the measurement problem of quantum mechanics.

References in corpus (22)

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• Generalized elimination of the global translation from explicitly correlated Gaussian functions
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Cited by in corpus (31)

• Non-adiabatic, Relativistic, and Leading-order QED Corrections for Rovibrational Intervals of ${}^4$He${}_2^{+}$ ($X{}^2{\Sigma }_{\mathrm{u}}^{+}$)
• Efficient geometric integrators for nonadiabatic quantum dynamics. II. The diabatic representation
• All-order relativistic computations for atoms and molecules using an explicitly correlated Gaussian basis
• Effective non-adiabatic Hamiltonians for the quantum nuclear motion over coupled electronic states
• Variational Dirac-Coulomb explicitly correlated computations for atoms and molecules
• Precise computation of rovibronic resonances of molecular hydrogen: $EF{}^1{\Sigma }_{\mathrm{g}}^{+}$ inner-well rotational states
• Non-adiabatic mass-correction functions and rovibrational states of ${}^4$He${}_2^{+}$ ($X{}^2{\Sigma }_{\text{u}}^{+}$)
• Second-order self-consistent field algorithms: from classical to quantum nuclei
• Non-adiabatic mass correction to the rovibrational states of molecules. Numerical application for the H${}_2^{+}$ molecular ion
• Non-adiabatic mass correction for excited states of molecular hydrogen: improvement for the outer-well $H\bar{H}{}^1{\Sigma }_{\mathrm{g}}^{+}$ term values
• Variational versus perturbative relativistic energies for small and light atomic and molecular systems
• The Bethe-Salpeter QED wave equation for bound-state computations of atoms and molecules
• Evaluation of the Bethe logarithm: from atom to chemical reaction
• Vibronic mass computation for the $EF$-$GK$-$H\bar{H}$ ${}^1{\Sigma }_{\text{g}}^{+}$ manifold of molecular hydrogen
• Pre-Born-Oppenheimer energies, leading-order relativistic and QED corrections for electronically excited states of molecular hydrogen
• Relativistic two-electron atomic and molecular energies using $LS$ coupling and double groups: role of the triplet contributions to singlet states
• Orientational decoherence within molecules and emergence of the molecular shape
• Lower bounds on par with upper bounds for few-electron atomic energies
• Pre-Born-Oppenheimer Dirac-Coulomb-Breit computations for two-body systems
• Laser-induced dynamic alignment of the HD molecule without the Born-Oppenheimer approximation
• Benchmark potential energy curve for collinear H${}_3$
• Gaussians for Electronic and Rovibrational Quantum Dynamics
• One-particle operator representation over two-particle basis sets for relativistic QED computations
• The MC-QTAIM: A framework for extending the atoms in molecules analysis beyond purely electronic systems
• Binding of muonated hydrogen molecules on the occasionof the Born-Oppenheimer approximation 90th anniversary
• Reaching precise proton affinities in non-Born-Oppenheimer calculations
• Integrals for lower bounds to the exact energy
• Characterization of the continuous transition from atomic to molecular shape in the three-body Coulomb system
• Rovibrational computations for He${}_2^{+}$ X ${\Sigma }_{\mathrm{u}}^{+}$ including non-adiabatic, relativistic and QED corrections
• Artificial versus Natural Atoms: The uncanny capability of the many-body Schrödinger equation to produce emergent behavior
• Double-pair Coulomb and Breit photon correction to the correlated relativistic energy