Energy spectrum of hydrogen-like atoms in a strong magnetic field

An expression for the energy spectrum of hydrogen-like atoms in strong magnetic fields is derived in terms of the energy spectrum of hydrogen. The development of a parametric expression for the latter is thus motivated. We present such an expression for the ground-state energy of hydrogen in magnetic fields B gauss, obtained by least-squares fittings of numerical results obtained previously from a variational calculation. Subject headings: magnetic fields - Zeeman effect