TRENDS IN VALENCE AUTOIONIZING RYDBERGS FOR ND(5) SEMIFILLED-SHELL GROUND AND EXCITED ATOMS AND IONS - CR, MN, MN+, FE+, FE2+, MO, TC, TC+ AND RE

New regularities are reported for valence-shell autoionizing nd --> n' p Rydbergs decaying to a continuous spectrum of the (n + 1)s(q) valenc e subshell of free metal atoms and ions with nd(5) semifilled subshell s: Cr(3d(5)4s(1) S-7), Mn(3d(5)4s(2) S-6), Mn+(3d(5)4s(1) S-7), Fe+(3d (5)4s(2) S-6), Fe2+(3d(5)4s(1) S-7), Mo(4d(5)5s(1) S-7), Tc(4d(5)5S(2) S-6), Tc+(4d(5)5s(1) S-7) and Re(5d(5)6s(2) S-6). We,predict an extre me narrowing for the nd --> n'p autoionizing Rydbergs in the nd(5) ato ms and ions with a ground-state nd(5) (n + 1)s(q=1) S-7 valence-shell configuration. In contrast, incomparably broader Rydbergs occur in bot h atoms and ions with a ground configuration nd(5) (n + 1)s(q=2) S-6, or in metastable atoms and ions whose electron configuration is nd(5) (n + 1)s(q=1) S-5. We also predict a drastic difference between the nd --> n'p Rydberg profiles in partial (n + 1)s up arrow and (n + 1)s do wn arrow photoionization cross sections of the nd(5) atoms and ions wi th a closed (n + 1)s(2) valence subshell (arrows up arrow and down arr ow show the two possible spin orientations for the ejected photoelectr ons). The regularities disappear for atoms and ions with other than an nd(5) semifilled subshell. The research is performed within both the 'spin-polarized' Hartree-Fock approach and the 'spin-polarized' random -phase approximation with exchange.