Anticrossing effects in odd Rydberg states of Li in the presence of a magnetic field

Odd Rydberg states of lithium in a uniform magnetic field have been excited from the ground state by sigma polarised light. In the recorded energy range, as the field strength increases, several adjacent diamagnetic n manifolds overlap and narrow anticrossings are observed. In spite of the small value of the quantum defect involved ( delta p =0.053), the core effects are responsible for the major part of the recorded anticrossing widths.