# Regarding lattice command

Hello lammps users
I am using Cu system with its orientation as:
lattice fcc 3.6323 orient x 1 -1 0 orient y 1 1 1 orient z -1 -1 2

##in log file
lattice spacing in x,y,z= 5.13685 6.29133 5.93152

I want to know do this represent interplanar distance?
Because interplanar distance between planes is given by d = a/sqrt(h^2 +k^2+l^2)

Could you throw some light how it is different from interplanar distance?

The lattice command doc page explains carefully
what the lattice spacing values mean and how
LAMMPS calculates them.

Steve

However during simulation on two different orientation, I am getting the outcome which I think should have otherwise.

(111) is highest density plane and [110] is the densest cutting direction and also (111) interplanar distance is lowest.
The no. of created atoms should have been larger in case of (111)[1-10], but it is coming lower than that of second case.

#######For (111)[1-10]crystal orientation,
region work block 0 300 0 120 -88.97281593 88.97281593 units box
lattice fcc 3.6323 orient x 1 -1 0 orient y 1 1 1 orient z -1 -1 2
â€”Created 539446 atoms

######and for (010)[100] orientation,
region work block 0 300 0 120 -90.8075 90.8075 units box

lattice fcc 3.6323 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1

Created 556100 atoms

What could be the reason for low atomic density in the first case?
Kindly throw some light.

I think you should read the lattice doc page carefully and
expt with a much smaller system to figure out and verify
what it is doing. So you can easily viz the results for a single
2d layer or two. Unless there is a bug (unlikely) the
lattice command is doing exactly what the doc page explains
(which can be tricky for different orientations).

Steve