Hello, In order to clarify: There are several ways to specify the coordinates to PWSCF/QE:
- In ?ngstr?m - In Bohr - In units of lattice constant, 'celldm(1)' in Bohr or 'a' in ?ngstr?m - In units of lattice vectors This you can choose on the line containing 'ATOMIC_POSITIONS'. Like noted above, one can use 'celldm(1:6)', alternatively 'a', 'b' and 'c' (plus 'cosab', 'cosac', 'cosbc') if you want to use ?ngstr?ms instead. Please have a look in the documentation, in particular 'INPUT_PW.*', below the section 'ibrav'. One more to specify the cell vectors is 'ibrav = 0' and the section 'CELL_PARAMETERS'. Hopefully this helps. Greetings, apsi -=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=- Ari P Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/ Physikalisch-Chemisches Institut der Universitaet Zuerich Tel: +41 44 63 54 497 / Mobile: +41 79 71 90 935 On Thu, 25 Oct 2012, Gisela Bocan wrote: > Hi, > ???? If I am not mistaken, every coordinate should be in celldm(1) units. > celldm(1) should be in bohr, so, if you have a coordinate X in Ang you should > write X_bohr/celldm(1) (where X_bohr > is X converted to bohr). > > Hope it helps! > Bye! > Gisela. > > On Thu, Oct 25, 2012 at 4:09 PM, Bodiford, Nelli K <nelli.bodiford at > mavs.uta.edu> wrote: > Celldm should be in Bohr, that's what I have been using and it works. > Hope it helps! > > On Oct 25, 2012, at 1:54 PM, David Furman wrote: > > Dear Espresso fans, > ? > I would like to make a series of calculations in different lattice parameter > values. > If I understand correctly, the atomic positions should be in units of the > lattice parameter "a" (default) in order for them to stay the same for every > lattice parameter. > So, I assume each Cartesian coordinate in Ang should be a fraction of lattice > parameter: X/a > But, does the lattice parameter should be in bohr (like in celldm(1)) or in > Ang as well ? > ? > Thank you > ? > ? > ? > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > > > >