[lammps-users] displace box triclinic box

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1

Hi ,
I have a question about the triclinic box:
I use
displace_box all xy final 0.1357393958 x final 0 5.430424202 y final 0 5.42872746 z final 0 5.430848568 units box
command to deform the box. Simulation box originally cubic with lattice constant 5.430
I have also dump the coordinates just after the defromation and when I check the positions I realized this:
ITEM: BOX BOUNDS xy xz yz
0 5.56616 0.135739
0 5.42873 0
0 5.43085 0
ITEM: ATOMS id type x y z

According to the manual and previous discussions about this topic suggest that first column
will be xlo, ylo and zlo respectively.
Second column will be xhi,yhi,zhi respectively. And the third column is
xy , xz yz
The question is I have set x side of the box with 0 to 5.430424202 but according to the positions data system set this to a higher value 5.6616.
When I submit this command what would be the matrice which represents edge vectors (primitive vectors) of the system?

2

Think of the 1st 2 columns of BOX BOUNDS as a rectangular bounding
box on the tilted box. This is useful for viz programs that
need that to draw the atoms. So in this case the 5.56 is
your 5.43 + 0.135.

See the region prism command doc page for explanation
of the edge vectors for the parallelipiped. You would have
to back those out of the bounding box. Or you can print
them directly with thermo output (vol, lx, ly, lz, xy, etc).

Steve