journal of kerbala university

The low-lying collective levels in 166-180Hf isotopes are investigated in the frame work of the interacting boson model (IBM-1). The contour plot of the potential energy surfaces, V (), shows two wells on the prolate and oblate sides which indicate that all hafnium nuclei are deformed and have rotational characters. The levels energy, electromagnetic transition rates B(E2) and electric quadrupole moment [ ] are calculated. All calculated values are compared with the available experimental data and show reasonable agreement