Pseudospectral Calculation of Helium Wave Functions, Expectation Values, and Oscillator Strength

@article{Grabowski2011PseudospectralCO,
  title={Pseudospectral Calculation of Helium Wave Functions, Expectation Values, and Oscillator Strength},
  author={Paul E. Grabowski and David F Chernoff},
  journal={Physical Review A},
  year={2011},
  volume={84},
  pages={042505}
}
We show that the pseudospectral method is a powerful tool for finding precise solutions of Schroedinger's equation for two-electron atoms with general angular momentum. Realizing the method's full promise for atomic calculations requires special handling of singularities due to two-particle Coulomb interactions. We give a prescription for choosing coordinates and subdomains whose efficacy we illustrate by solving several challenging problems. One test centers on the determination of the… 
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