Explicitly correlated Gaussian functions with shifted-center and projection techniques in pre-Born-Oppenheimer calculations

Andrea Muolo, E. Mat́yus, Markus Reiher

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Numerical projection methods are elaborated for the calculation of eigenstates of the non-relativistic many-particle Coulomb Hamiltonian with selected rotational and parity quantum numbers employing shifted explicitly correlated Gaussian functions, which are, in general, not eigenfunctions of the total angular momentum and parity operators. The increased computational cost of numerically projecting the basis functions onto the irreducible representations of the three dimensional rotation-inversion group is the price to pay for the increased flexibility of the basis functions. This increased flexibility allowed us to achieve a substantial improvement for the variational upper bound to the Pauli-allowed ground-state energy of the H3+={p+,p+,p+,e-,e-} molecular ion treated as an explicit five-particle system. We compare our pre-Born-Oppenheimer result obtained for this molecular ion with rotational-vibrational calculations carried out on a potential energy surface.

Original languageEnglish
Article number184105
JournalJournal of Chemical Physics
Volume149
Issue number18
DOIs
Publication statusPublished - Nov 14 2018

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projection
molecular ions
flexibility
parity
eigenvectors
Ions
Hamiltonians
Potential energy surfaces
Angular momentum
Eigenvalues and eigenfunctions
Ground state
quantum numbers
angular momentum
potential energy
inversions
costs
operators
ground state
Costs
energy

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this

Explicitly correlated Gaussian functions with shifted-center and projection techniques in pre-Born-Oppenheimer calculations. / Muolo, Andrea; Mat́yus, E.; Reiher, Markus.

In: Journal of Chemical Physics, Vol. 149, No. 18, 184105, 14.11.2018.

Research output: Contribution to journalArticle

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