An operational scheme to determine the locally preferred structure of model liquids

We present an operational method to determine the 'locally preferred structure'' of model liquids, a notion often put forward to explain supercooling of a liquid and glass formation. The method relies on finding the global minimum in the (free) energy landscape of clusters of atoms or molecules embedded in a liquid-like environment. We propose a more systematic approach of the external potential mimicking the influence of the surrounding bulk liquid on the cluster than in our previous work [S. Mossa and G. Tarjus, J. Chem. Phys 119, 8069 (2003)]. The procedure is tested on the one-component Lennard-Jones liquid and we recover, without a priori input, that the locally preferred structure is an icosahedral arrangement of thirteen atoms.