about simulation combine after different process do

Dear lammps experts,

I have a problem with this.

I want to do a process below.

1.let Cu metal on nvt 300 to balance,and then npt to 1500 to heat it ,and then nvt to 300 to let temperature to down ,and balance it 300K. >>>>>get the file restart

2.let Al metal on nvt 300 to balance,and then npt to 935 to heat it,and then nvt to 300 to let temperature to down,and balance it 300K >>>>>>get the file restart

3.combine them and both of them on npt to 2000 to heat it , and then nvt to 300 to let temperature to down,and balance it 300K

It is possible to do this process?

because I do this process but I merge them I will see the not fcc and many others in themselves

best regards,lulu

technically, the answer is “yes”. however, there are some possible problems. e.g. if you have periodic boundary conditions, you have to adjust the box when merging and possibly also positions to avoid overlaps. also when running different systems with npt, they may expand differently.

talking about npt, it seems odd that you are using fix npt for heating, but not for cooling, so the resulting system will be at the expanded high-temperature volume. but since you also want to heat the combined system, the question is, why process each system separately first?

why not create the combined system right away and then do step 3 right away? or, if so desired, do heating to 2000K individually (you can assign a group to each part and then run fix nvt only on one part and leave the other immobile) and then switch to run the combined system with fix npt.

axel.