Structure of 60,62Fe and the onset of vg9/2 occupancy

Level structures in Fe-60,62(34,36) and adjacent nuclei were studied with Gammasphere using the reaction of a 430-MeV Ni-64 beam on a 55-mg/cm(2) thick U-238 target. High-spin level schemes were deduced from singly- and doubly-gated prompt coincidence events. Levels populated in the beta decay of Mn-60,Mn-62 isomers were studied in singly-and doubly-gated delayed coincidences. Spin and parity assignments were deduced from angular correlations of gamma rays observed in both nuclei, leading to firm positive-parity yrast assignments up through 8(+) in Fe-62. The observed levels for Fe-60 up to similar to 3.5 MeV compare well with pf shell-model calculations available in the literature. Calculations performed in a limited pfg basis exhibit reasonable agreement for the 2(+), 4(+), and 6(+) levels in Fe-62. However, theoretical descriptions that include the newly identified negative-parity levels in Fe-62 require a much larger basis, necessarily including g(9/2) neutrons, as well as improved interactions leading to negative-parity levels.