Author Topic: Geometry optimization, lattice vectors  (Read 3024 times)

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Offline jrussell

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Geometry optimization, lattice vectors
« on: May 30, 2012, 20:10 »
Dear ATK, I am a little confused about how to perform a geometry optimization where both cartesian coordinates and lattice vectors are optimized. Is this method still valid: http://quantumwise.com/forum/index.php?topic=29.msg77#msg77 Or is optimization of lattice vectors implied when you use disable_stress=false  in the OptimizeGeometry part of the input file?
Code
bulk_configuration = OptimizeGeometry(
        bulk_configuration,
        max_forces=0.05*eV/Ang,
        max_stress=5.0e-3*Units.eV/Units.Ang**3
        max_steps=2000,
        max_step_length=0.5*Ang,
        trajectory_filename='wire3-5traj.nc',
        disable_stress=False,
        optimizer_method=QuasiNewton(),
        )
I really appreciate the help! Sincerely, John

Offline Anders Blom

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Re: Geometry optimization, lattice vectors
« Reply #1 on: May 30, 2012, 22:46 »
No, the link you refer to is outdated. It was for an older version of ATK that did not implement the computation of the stress.

So for the current ATK, you are correct that the lattice vectors will be optimized if disable_stress is False.