We studied in a microscopic multiphonon approach the proton-neutron symmetry
and phonon structure of some low-lying states recently discovered in 92Zr. We
confirm the breaking of F-spin symmetry, but argue that the breaking mechanism
is more complex than the one suggested in the original shell model analysis of
the data. We found other new intriguing features of the spectrum, like a
pronounced multiphonon fragmentation of the states and a tentative evidence of
a three-phonon mixed symmetry state.Comment: 13 pages, to appear in Phys. Rev.
