Development of a ReaxFF Reactive Force Field for ternary phosphate-based bioactive glasses: input and analysis codes

Input and analysis codes to accompany the paper "Development of a ReaxFF Reactive Force Field for ternary phosphate-based bioactive glasses". Not all output files are included for space reasons, but the files given are sufficient to reproduce the methodology in the paper.

Abstract of paper:

Phosphate-based glasses (PBGs) in the CaO-Na2O-P2O5 system have diverse applications as biomaterials due to their unique dissolution properties. A reactive force field (ReaxFF) has been developed to simulate these materials at the atomic level. The ReaxFF parameters of PBGs, including the interaction between phosphorus and calcium atoms, have been developed using a published code based on genetic algorithms. The training data, including the atomic charges, atomic forces, bond and angle parameters and different differential energies are chosen and measured from static quantum-mechanical calculations and ab initio molecular dynamics of PBGs. We did different short- and medium-range structural analysis on the bulk simulated PBGs with different compositions to validate the developed potential. Radial and angular distribution functions and coordination numbers of network formers and modifiers as well as the network connectivity of the bioglass are in agreement with experimental and previous simulations using both shell-model classical force fields and ab initio simulated data; for example, the coordination number of phosphorus is 4.0. This successful development of ReaxFF parameters being able to describe the bulk PBGs enables us to work on dissolution behaviour of the glasses including the interaction of water molecules with PBGs in future works.