Dear All, I want to do phonon calculation on an adsorption system with symmetry. So I did some test calculations below.
I did a test calculation on a system, say H2O in the cubic cell, with ph.xand only gamma point (both in scf and phonon ). At first, I calculated all the representations. Then ph.x calculated 3*3=9 representations (9 SCF calcuclation). But why not calculated only 6 representations because of the symmetry? Then I set nat_todo=1 and let only the first H atom to move. But the program calculated both two H atoms, and 6 representations (for 2 H ) are calculated. Why not only calculated only the first 3 representations of the first H? (nrapp can be used to fix the representations to be done, this may be a resolution for this problem?) Thank you for your reply in advance! Yours, zhu -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/attachments/20060725/ad6e9455/attachment.htm
