Since the first attempts to calculate the helium ground state in the early days of Bohr-
Sommerfeld quantization, two-electron atoms have posed a series of unexpected …

Using theoretical results from complex rotation calculations and data from experimental
photoionization cross sections, the quantum defects, the widths, the oscillator strengths and …

The concerted motion of two or more bound electrons governs atomic and molecular, non-
equilibrium processes including chemical reactions, and hence there is much interest in …

A triple basis set in Hylleraas coordinates is used to obtain improved variational bounds for
the nonrelativistic energy and other properties of He, H−, and Ps−. The accuracy, numerical …

This book describes the manifestations of chaos in atoms and molecules. The study of chaos
is today one of the most active and prolific areas in atomic physics. This is the first attempt to …

Essentially exact calculations of the nonrelativistic wave functions and energies of helium
are reviewed, together with the lowest-order relativistic corrections. The results are extended …

We give a detailed account of an ab initio computational treatment of multiphoton single
ionization (with or without excitation) as well as double ionization of two-electron atoms …

We present an analytical model capable of describing two-photon ionization of atoms with
attosecond pulses in the presence of intermediate and final isolated autoionizing states. The …

Gross–Oliveira–Kohn (GOK) ensemble density-functional theory (GOK-DFT) is a time-
independent extension of density-functional theory (DFT) which allows the computation of …

Two first-principles simulation techniques, path integral Monte Carlo (PIMC) and density
functional molecular dynamics (DFT-MD), are applied to study hot, dense helium in the …