# 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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