Dear Dr. Dubbeldam,

To estimate self-diffusion coefficients, I employed RASPA to perform molecular dynamics simulations, followed by calculating the slope of the mean square displacement with respect to the simulation time.

However, the result obtained from the MD simulation, as shown in the plot given in the attachment, shows that there is no strong linear relationship between MSD and time.

I want to know why it obtained such results and how to get an accurate linear relationship between them.

Best regards.