Non-zero angular momentum states of the helium atom in a strong magnetic field

The electronic structure of the helium atom in the magnetic field regime B = 0-100 au is investigated, using a full configuration-interaction approach which is based on a nonlinearly optimized anisotropic Gaussian basis set o f one-particle functions. The corresponding generalized eigenvalue problem is solved for the magnetic quantum number M = -1 and for both even and odd z-parity as well as singlet and triplet spin symmetry Accurate total electr onic energies of the ground state and the first four excitations in each su bspace as well as their one-electron ionization energies are presented as a function of the magnetic field. Additionally we present energies for elect romagnetic transitions within the M = -1 subspace and between the M = -1 su bspace and the M = 0 subspace treated in a previous work. A complete table of wavelengths and field strengths for the detected stationary points is gi ven.