Geometry Optimisation with CASTEP
Geometry Optimisation with CASTEP
Geometry Optimisation with CASTEP
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There is an inital dip in the forces at around iteration 14 as some search direction is tried but this causes<br />
an increase in the energy. Then there is a large increase in the forces (presumably due due dimer<br />
attraction) accompanied by a large energy gain which are due to dimerisation. There is then a small peak<br />
in the forces and the energy at about iteration 24 as the energy barrier to asymmetric dimerisation is<br />
overcome.<br />
In summary, this example has illustrated the use of constraints upon atomic positions and has also looked<br />
at hydogen passivation and the variation of both the number of layers of atoms and the thickness of the<br />
vacuum gap as ways to deal <strong>with</strong> aperiodic supercell configurations such as surfaces.<br />
Next: References Up: <strong>Geometry</strong> <strong>Optimisation</strong> <strong>with</strong> <strong>CASTEP</strong> Previous: A Variable Cell calculation<br />
2005-04-03