High-spin proton alignments and coexisting coupling schemes in Hf168

High-spin states in Hf168 were populated in the Zr96(Ge76,4n) reaction and the decay γ rays measured with the Gammasphere spectrometer array. Previously known bands were extended to significantly higher spins and seven new bands were established. The results were interpreted within the framework of the cranked shell model with the help of comparisons with neighboring nuclei. The observation of full alignment in band crossings at a rotational frequency ω~0.55 MeV revealed that these crossings are associated with proton alignments involving h11/2 and h9/2 orbitals. The characteristics of one strongly coupled high-K band indicate that the deformation-aligned configuration is built on the same six quasiparticles that constitute the high-spin structure of a rotationally aligned band. This leads to the coexistence of two coupling schemes, deformation and rotation alignment, in six-quasiparticle structures involving the same orbitals.