Fully numerical Hartree‐Fock and density functional calculations. II. Diatomic molecules

@article{Lehtola2018FullyNH,
  title={Fully numerical Hartree‐Fock and density functional calculations. II. Diatomic molecules},
  author={Susi Lehtola},
  journal={International Journal of Quantum Chemistry},
  year={2018}
}
  • S. Lehtola
  • Published 27 October 2018
  • Chemistry
  • International Journal of Quantum Chemistry
We present the implementation of a variational finite element solver in the HelFEM program for benchmark calculations on diatomic systems. A basis set of the form $\chi_{nlm}(\mu,\nu,\phi)=B_{n}(\mu)Y_{l}^{m}(\nu,\phi)$ is used, where $(\mu,\nu,\phi)$ are transformed prolate spheroidal coordinates, $B_{n}(\mu)$ are finite element shape functions, and $Y_{l}^{m}$ are spherical harmonics. The basis set allows for an arbitrary level of accuracy in calculations on diatomic molecules, which can be… 

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