Study of Lennard-Jones clusters: Effects of anharmonicities far from saddle points
نویسندگان
چکیده
Abstract We study the transition pathways of a Lennard-Jones cluster of seven particles in three dimensions. Low lying saddle points of the LJ cluster, which can be reached directly from a minimum without passing through another minimum, are identified without any presumption of their characteristics, nor of the product states they lead to. The probabilities are computed for paths going from a given minimum to the surrounding saddle points. These probabilities are directly related to prefactors in the rate formula. This determination of the rate prefactors includes all anharmonicities, near or far from saddle points, which are pertinent in the very sophisticated energy landscape of LJ clusters and in many other complex systems.
منابع مشابه
Transition rate prefactors for systems of many degrees of freedom.
When a minimum on the potential energy surface is surrounded by multiple saddle points with similar energy barriers, the transition pathways with greater prefactors are more important than those that have similar energy barriers but smaller prefactors. In this paper, we present a theoretical formulation for the prefactors, computing the probabilities for transition paths from a minimum to its s...
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