RDM: An R interface for high-throughput simulation of ion-material interactions using TRIM

Abstract

The quantitative estimation of the damage caused by ion-material interaction is carried out using Monte Carlo codes as, for instance, TRIM (TRansport of Ions in Matter). Some studies require multiple simulations to be run, varying the ion energy, mass, and charge, or changing the target material. Natural radiation damage in minerals due to the alpha decays in the three natural series is an example. In such applications, the task of calculating the ion damage on the material becomes very time-consuming. The R language code presented in this paper, Radiation Damage in Materials (RDM), is designed to serve as an interface to set parameters, start, collect, and treat the results of multiple TRIM simulations. The main outputs of RDM are the dpa (displacements per atom) and dpa profiles for ion beam irradiation, and, if needed, the natural radiation dpa for any materials to be used in a given study. The fluence of an artificially accelerated ion beam matching the natural radiation dpa is also calculated for studies in which swift heavy ions are used as proxies for natural radiation damage. Program summaryProgram Title: Radiation Damage in MaterialsCPC Library link to program files:https://doi.org/10.17632/jxrt58jprt.1Developer's repository link:https://sites.ifi.unicamp.br/cronologia/rdm/Licensing provisions: GPLv3Programming language: RNature of problem: The calculation of the damage caused in materials by the interaction with ions is a necessary task for planning and interpreting ion beam experiments. Calculations are carried out using the outputs of computer codes, as TRIM, available in the SRIM suit [1], which furnish the quantities of defects generated by the interaction of ions with target materials. Each simulation has to be set up in the TRIM interface or in an input file. If multiple simulations are needed, the time of preparing and running sequential simulations becomes prohibitive. This scenario will appear, for instance, when the effects of the natural radiation are to be calculated, in which case the damage caused by the yields of the alpha decays of the three natural decay series has to be calculated. In this particular application, researchers usually make approximations that are not always satisfactory.Solution method: A R code, Radiation Damage in Materials (RDM), was developed to make possible the high-throughput simulation of the interactions of ions with the matter, using TRI1M as the simulation engine. The code also facilitates the calculation of the natural radiation damage by solving the coupled differential equations for the natural decay chains and automatically queuing the necessary TRIM simulations. RDM is a web browser interface to start simulations and collect and treat simulation outputs. For researchers unfamiliar with TRIM, a stand-alone portable installation of RDM is available.Additional comments including restrictions and unusual features: Multi-threading is not currently included in the code. Therefore simulations run one by one and the Radiation Damage in Materials does not compute commands during simulations. The numerical solution for the radioactive series does not converge for a few specific values of U, Th, and Sm contents. This problem can be circumvented by multiplying the problematic contents by an arbitrary constant and dividing the dpa results by the same constant.