HIGH-RESOLUTION PHOTOELECTRON SPECTROMETRY OF ATOMIC MANGANESE FROM THE REGION OF THE 3P-]3D GIANT-RESONANCE TO 120 EV

Partial photoionization cross sections sigma of the 3d and the 4s main lines and the major satellite lines following the photoionization of atomic manganese in the vicinity of the 3p --> 3d giant resonance are studied in detail using the constant-ionic-state technique. Previously unresolved features are seen, revealing the complex structure of this transition-metal atom. Evidence for seven excited states hidden in th e giant-resonance region is uncovered. Widths of most of the observed excited states are deduced. The width of the dominant [Ne]3s(2)3p(5)3( d)64s2(6P) state is found to be at most 1.5 eV. The origin of a pronou nced dip in the partial cross section of the primary 3d photoionizatio n line, which also appears in absorption, is identified. More than 15 resonance features converging to the [Ne]3s(2)3p(5)3d(5)4s2(P-7(4,3,2) ) limits are observed, and tentative assignments are given. In additio n, nonresonant photoelectron spectra recorded from 80 to 120 eV photon energy are examined to determine the behavior of the strongest photoe lectron satellite lines and very-high-lying binding energy satellites, which, until now have not been investigated.