# 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} }

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…

## 21 Citations

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