$^{16}$O + $^{16}$O molecular structures of positive- and negative-parity superdeformed bands in $^{34}$S

The structures of excited states in $^{34}$S are investigated using the antisymmetrized molecular dynamics and generator coordinate method (GCM). The GCM basis wave functions are calculated via energy variation with a constraint on the quadrupole deformation parameter $beta$. By applying the GCM after parity and angular momentum projections, the coexistence of two positive- and one negative-parity superdeformed (SD) bands are predicted, and low-lying states and other deformed bands are obtained. The SD bands have structures of $^{16}$O + $^{16}$O + two valence neutrons in molecular orbitals around the two $^{16}$O cores in a cluster picture. The configurations of the two valence neutrons are $delta^2$ and $pi^2$ for the positive-parity SD bands and $pi^1delta^1$ for the negative-parity SD band. The structural changes of the yrast states are also discussed.