UT theoretical chemistry code forum

Dear Prof. Henkelman,

I used CI-NEB to find the mep for Li ion migration in a large bulk supercell.

I have checked the forum and found that to perform subsequent phonon frequency calculations, but such large bulk supercell has too many degrees of freedom.

Is it necessary to check all degrees of freedom for all atoms in such large bulk supercell?

Thanks

You can select degrees of freedom near the atoms that have moved in the reaction and look for convergence as you add more degrees of freedom. We have some scripts for this, such as dymseldisp.pl. Note that you can also combine dynamical matrix calculations with our code, and run any/all displacements in parallel.