Can we transform the non-orthogonal box into orthogonal box?

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1

Hello, everyone

I conbine the Kremer-Grest model(bead-spring polymer model) with the fix deform + nvt/sllod commad to study on NEMD simulations.
Then, I could get the atom’s unwrap coordinates
But if I want to restart the program, I must use the non-orthogonal box and the unwrap coordinates

In other words,
I couldn’t use the orthogonal box(this box is the original box before the NEMD) with the unwrap coordinates, the program would stop!

I’m not good at C++, so I couldn’t read the src files

So, my question is :
Is computer code for periodic boundariers different in non-orthogonal box?

As far as know, in orthogonal box, this code may be
R=R-boxl*anint(R/boxl), anint returns the nearest interger to X(, Page.30)

I don’t know the key words about this problem, I’m glad who answers my question or give me the reference

Best wishes

Yongjin Ruan

2

Maybe you are expecting to see the Lees-Edwards boundary condition, where the periodic cell remains orthorhombic, but each periodic image in y is shifted in x. Well, that is not how LAMMPS does it, instead it uses a tilted periodic cell. The behavior is identical to Lees-Edwards in most respects and is actually more general and less artificial. But once the initially orthorhombic cells is tilted, you can not untilt it.

Aidan