[Pw_forum] Question about vc-relax

[Joshua Young]

Hi QE community,

I am attempting to relax the lattice parameters and internal atomic
positions of monolayer MoS2 using a variable cell relaxation. However,
although the atom positions will change over the course of the calculation,
the lattice parameters do not even though the calculation converges. I have
attached my input file here, as well as the atomic positions and lattice
parameters output for five steps of the calculation. I am including van der
Waals correction, spin-orbit coupling, and using fully relativistic
pseudopotentials.

Could this be because I have started from lattice parameters which are
close to the equilibrium values of MoS2? Or do I simply have a tag wrong in
the input file?

Any help would be greatly appreciated.

Thank you,
Joshua Young, PhD
Postdoctoral Research Associate
Naval Research Laboratory
Washington, DC
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20161014/4846a046/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mos2_atomic_positions_change.out
Type: application/octet-stream
Size: 1605 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20161014/4846a046/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mos2_cell_relax.in
Type: application/octet-stream
Size: 1410 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20161014/4846a046/attachment-0001.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mos2_lattice_parameter_change.out
Type: application/octet-stream
Size: 779 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20161014/4846a046/attachment-0002.obj>