R/activationFreeEnergy.R

In ChargeTransport: Charge Transfer Rates and Charge Carrier Mobilities

activationFreeEnergy <- function(lambda, dE0 = 0, dEField = 0){
  if(missing(lambda))
    stop("Please specify the reorganization energy (lambda)")
  
  args <- list(
    lambda = lambda,
    dE0 = dE0,
    dEField = dEField)
  
  are.list <- sapply(args, is.list)
  if(any(are.list))
    stop("Arguments must be vectors, matrices or data.frames")
  
  are.data.frame <- sapply(args, is.data.frame)
  args[are.data.frame] <- lapply(args[are.data.frame], as.matrix)
  
  are.numeric <- sapply(args, is.numeric)
  if(any(!are.numeric))
    stop("Arguments must be numeric")
  
  are.scalar <- sapply(args, function(x) return(length(x) == 1))
  
  lengths <- sapply(args[!are.scalar], length)
  dims    <- lapply(args[!are.scalar], dim   )
  
  if(length(lengths) != 0)
    if(!all(sapply(dims, identical, dims[[1]])) | !all(sapply(lengths, identical, lengths[[1]])))
      stop("Arguments must be scalars or have the same dimensions and lengths")
  
  dE <- (args$lambda + args$dE0 + args$dEField)^2/(4*args$lambda)
  
  return(dE)
}