[lammps-users] create_atoms + basis command

Dear LAMMPS-users,

I’m trying to create a hcp-structure where the first basis atom should be assigned to W and the second basis atom should be assigned to C. In order to do this I specified my custom lattice vectors and corresponding basis, but when I try use the “create_atoms 1 region box basis 1 1” for the W-atoms it places W on the second basis as well. I interpret the command in the documentation as follow : I assign the type 1 atoms to the first basis atom in the corresponding box lattice. Obviously I’m doing something wrong here. I would appreciate any suggestions, since I clearly am misunderstanding the documentation. Thanks in advance.

Best regards,

Assuming W = type 1 and C = type 2 as the 2 basis atoms
in your lattice command. Then you want to use basis 1 1 basis 2 2
in your create_atoms command, meaning the 2nd basis atom
is assigned to type 2. You could leave off basis 1 1 since its
the default. Note that the only thing that makes one atom
a W vs a C is the type assignment.