Dear All
I found that the strain rates for simulating tension or shear at the atomic scale are very high, generally reaching around 10 ^ 10 s-1 (0.01 ps-1), while the highest strain rate at the macroscopic scale is only 10 ^ 3 s-1. Could anyone tell me why the strain rate at the atomic scale needs to be so high?
Thanks
This issue stems quite naturally in molecular simulation and has been discussed since the dawn of time in molecular dynamics applied to material science.
I encourage you to look for typical atom vibration frequencies, understand how time steps value are generally computed with regard to these frequency values, and compare them with macroscopic experimental time scales (take the minute for example). You’ll get an idea of the number of integration steps required to reach experimental strain rates using MD simulations, something you can compare with actual computer capabilities for small system of thousands atoms.