title: Determination of best-fit potential parameters for a reactive force field using a genetic algorithm.
abstract: The ReaxFF interatomic potential, used for organic materials, involves more than 600 adjustable parameters, the best-fit values of which must be determined for different materials. A new method of determining the set of best-fit parameters for specific molecules containing carbon, hydrogen, nitrogen and oxygen is presented, based on a parameter reduction technique followed by genetic algorithm (GA) minimization. This work has two novel features. The first is the use of a parameter reduction technique to determine which subset of parameters plays a significant role for the species of interest; this is necessary to reduce the optimization space to manageable levels. The second is the application of the GA technique to a complex potential (ReaxFF) with a very large number of adjustable parameters, which implies a large parameter space for optimization. In this work, GA has been used to optimize the parameter set to determine best-fit parameters that can reproduce molecular properties to within a given accuracy. As a test problem, the use of the algorithm has been demonstrated for nitromethane and its decomposition products.
authors.affiliation: Computational Analysis Division, Bhabha Atomic Research Centre, Visakhapatnam, India. poonam.pahari@gmail.com
authors.forename: Poonam
authors.initials: P
authors.lastname: Pahari
authors.forename: Shashank
authors.initials: S
authors.lastname: Chaturvedi
mesh_terms: D000465:Algorithms; D008697:Methane / Q000031:analogs & derivatives / Q000737:chemistry; D008722:Methods; D009595:Nitroparaffins / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*
chemical_list: D009595:Nitroparaffins; D009930:Organic Chemicals; D008697:Methane; C008640:nitromethane