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Mixed-symmetry 2' states are identified in vibrational-like nuclei lying between the 2 = 2 0 and 28 closed shells. The M1 strengths of 2t-2+ transitions are obtained from level lifetimes and y-ray multipole mixing ratios. The latter were measured using the directional distribution of y-rays from an oriented source (56Fe) and y y directional correlations on cascades which follow neutron capture ("Ti, "Cr and 58Fe). There is strong evidence for the sharing the characteristics of the mixed-symmetry 2t level with neighbouring 2+ levels. The identification of a 4+-4+ transition with a large B(M1) value in S6Fe indicates the need for g-bosons in the IBA-2 which is used as a framework for discussing the data. RADIOACTIVITY 56Mn(/?, Y ) ' ~F ~, cryogenically oriented nuclei; measured y(6); deduced 6. NUCLEAR REACTION 47Ti, 53Cr and "Fe (n, y ) ; enriched target, online directional correlations; measured yy(6); deduced 6.

Mixed-symmetry assignments are made to the 1.570 (l;), 1.573 (2:) and 1.659 (3:) MeV levels in 2wHg. The characteristics of the 2: level are shared with nearby 2+ levels at 1.254 and 1.593 MeV. An interacting boson approximation (IBA-2) analysis examines the sensitivity of the mixed-symmetry states to the E, parameters of the Majorana term and finds that both the magnitude and sign of the d(E2iM1) mixing ratio of 2' -2: transitions are well reproduced at the values of the tt parameters used to obtain a level energy fit. The IBA-2 calculations also give a satisfactory fit to the energy levels and in general provide X(EOiE2) values close to the experimental data. These calculations agree with the known oblate deformation of the ground state which we find to be predicted by Kumar's dynamic deformation model.Experimental data from n, yy(0) experiments together with internal conversion coefficient (ICC) results allow 1+ levels to be unambiguously established at 1.570, 1.631, 1.718, 2.061, 2.370, 2.640 and 2.979 MeV. The measurements also provide precise 6 values of many transitions while event-by-event coincidence information permits the decay scheme to the developed with previous unlocated transitions now firmly assigned. NUCLEAR REACTIONS '99Hg(n; y)ZWHg; thermal neutrons, measured I,, y-ray coincidences, yy(8); deduced 6(E2/Ml), X(EOIE2), mixed-symmetry states, level scheme; enriched target, Ge(Li) detectors. 3 3 0

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