MOLECULAR DYNAMICS SIMULATION DEVICE, METHOD, AND PROGRAM

摘要

[PROBLEMS] To efficiently reproduce a structural change of a substance having complex composition containing multiple elements mixedly accompanied by recombination of a covalent bond in molecular dynamics simulation of a large-scale system in which more than several thousands of atoms are handled and to reproduce the structure energy change dependent on the coordination state of each atom with high fidelity. [MEANS FOR SOLVING PROBLEMS] The motion of an expanded mechanics system in which the atomic nucleus coordinates and an internal degree of freedom are combined is computed by the classical molecular dynamics method using an atomic model having a role of determining the covalent bond portion and the internal degree of freedom. With this, while resenting the manifestation of an attractive force interaction having an azimuth dependence like a covalent bond, its smooth rebonding can be expressed. The coordination state of each atom is judged from the location of the interatomic bond expressed by the method, and the potential constant different depending on the coordination state is used. As a result, the structure energy change depending on the dynamically changing coordination state which cannot be reproduced by conventional methods can be reproduced with high fidelity. A large-scale molecular simulation of a chemical change of a multiple element mixture system accompanied by recombination of a covalent bond can be carried out with high accuracy.