Programming and application of molecular dynamics simulation program based on Python

In this paper, a molecular dynamics simulation program is written in python, and the molecular system of He is studied in detail with this program.Different initial conditions, different boundary conditions and truncation points are studied respectively. Under the initial condition that the molecular number is 500 and the initial molecular velocity is 500, the system finally develops into a maxwell equilibrium system after 2.25 e-11 s.The influence of periodic boundary conditions and rigid boundary conditions on the development of the system is studied respectively.After studying the truncation point, it is found that it must be more than 1.1*sigma(sigma is a constant in l-j potential energy, which can be measured by experiments) as the truncation. If it is less than this value, the system will deviate from the physical reality due to numerical error. It is also found that the potential function has important influence on the development of the system.