%0 Journal Article %T Collective coordinates, shape transitions and shape coexistence: a microscopic approach %A Takashi Nakatsukasa %A Niels R. Walet %J Physics %D 1998 %I arXiv %R 10.1103/PhysRevC.58.3397 %X We investigate a description of shape-mixing and shape-transitions using collective coordinates. To that end we apply a theory of adiabatic large-amplitude motion to a simplified nuclear shell-model, where the approximate results can be contrasted with exact diagonalisations. We find excellent agreement for different regimes, and contrast the results with those from a more standard calculation using a quadrupole constraint. We show that the method employed in this work selects diabatic (crossing) potential energy curves where these are appropriate, and discuss the implications for a microscopic study of shape coexistence. %U http://arxiv.org/abs/nucl-th/9807078v1