Particle-hole ambiguity in the parameters of the microscopic interacting boson model

The parameters of the microscopic interacting boson model that emerge from a multi-nondegenerate-orbit theory are shown to depend on whether they are generated in terms of correlated pairs of particles or correlated pairs of holes. It is suggested that the ambiguity results from the shell-model truncation inherent in the interacting boson model and that it can be alleviated by including renormalization effects from outside the interacting boson model subspace. NUCLEAR STRUCTURE Microscopic interacting boson model; particle-hole ambiguity in model parameters.