Multiscale analytic continuation approach to nanosystem simulation: Applications to virus electrostatics

Abhishek Singharoy, Anastasia M. Yesnik, Peter Ortoleva
2010 Journal of Chemical Physics  
Electrostatic effects in nanosystems are understood via a physical picture built on their multiscale character and the distinct behavior of mobile ions versus charge groups fixed to the nanostructure. The Poisson-Boltzmann equation is nondimensionalized to introduce a factor that measures the density of mobile ion charge versus that due to fixed charges; the diffusive smearing and volume exclusion effects of the former tend to diminish its value relative to that from the fixed charges. We
more » ... uce the ratio of the average nearest-neighbor atom distance to the characteristic size of the features of the nanostructure of interest ͑e.g., a viral capsomer͒. We show that a unified treatment ͑i.e., ϰ͒ and a perturbation expansion around = 0 yields, through analytic continuation, an approximation to the electrostatic potential of high accuracy and computational efficiency. The approach was analyzed via Padé approximants and demonstrated on viral system electrostatics; it can be generalized to accommodate extended Poisson-Boltzmann models, and has wider applicability to nonequilibrium electrodiffusion and many-particle quantum systems.
doi:10.1063/1.3424771 pmid:20459161 pmcid:PMC2878355 fatcat:to4vlrvs4jfr7atru5gmpgvpfu