Shape-phase transitions in the vibron model and bent molecules

A mean field study of triatomic molecules in the vibron model is carried ou t. Analytical solutions for the mean fields are found, and shape-phase tran sitions in the model are investigated utilizing these solutions. The Majora na interactions are shown to play an essential role in driving the phase tr ansition from linear to bent shape. Results presented here will facilitate realistic studies of bent molecules within the symmetry-breaking approach. (C) 1999 Elsevier Science B.V. All rights reserved.