Abstract
The energies of the ground, beta and gamma bands as well as the associated B(E2) values have been calculated using interacting boson model (IBM). We have developed a new method called "new empirical equation" for each even-even rare-earth Er-Os for N = 100. Also, the relation of the gamma energy over spin as a function of the spin (I) (E-GOS) has been drawn. The ratio between the energies of the (I + 2) and (I) states as a function of I has been drawn to determine the property of the ground-state band, these curves indicated that these isotopes have a rotational property SU(3), with the X(5) property for Os-176 isotopes. The contour plots of the potential energy surface for Er-Os for N = 100 are studied using the simplified form of interacting boson model with an intrinsic coherent state. The critical points have been determined for Os-176 isotopes. The behaviors of energy and B(E2) ratios in the ground-state band are examined.