Optimising reaction coordinates for crystallisation by tuning the crystallinity definition

Author(s)
Swetlana Jungblut, Andreas Singraber, Christoph Dellago
Abstract

We apply maximum likelihood analysis to optimise crystallisation measures based on Steinhardt bond order parameters. Assuming that the size of the largest cluster of crystalline particles serves as a good reaction coordinate for the freezing transition, we write down the likelihood to observe the committor values computed for a large number of configurations. We then maximise the likelihood function by varying the parameters that enter the definition of crystallinity. For the crystallinity definition considered here this parameter set consists of the thresholds for the next-neighbour distance, the strength of the crystalline bonds and the number of crystalline connections. The optimum parameter set found by the likelihood maximisation differs considerably from the parameters that are commonly used, but leads only to a marginal improvement of the quality of the reaction coordinate.

Organisation(s)
Computational and Soft Matter Physics
Journal
Molecular Physics: an international journal in the field of chemical physics
Volume
111
Pages
3527-3533
No. of pages
7
ISSN
0026-8976
DOI
https://doi.org/10.1080/00268976.2013.832820
Publication date
12-2013
Peer reviewed
Yes
Austrian Fields of Science 2012
103036 Theoretical physics, 103015 Condensed matter, 103029 Statistical physics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/c9ece3e3-92ce-4973-8e1f-9944174e36f9