ecutwfc determines the size of the plane wave you are using for your cal. (Note that PWscf is a plane wave based code, i.e., the wave functions are expanded in a plane wave basis).
If you use ultrasoft pseudopotential, you introduce augmentation charges (because norm-conserving condition is not satisfied by these pp's). For those one uses ecutrho. In your case you are using norm-conserving pseudopotentials. Therefore for ecutrho you can use the default value (ecutrho=4*ecutwfc). However, it is better to use ultrasoft PP because you need lower value of ecutwfc, i.e., fewer no. of plane waves and therefore faster calculations. There are plenty of good books & papers available. Please go through them before you do the cal. or ask ur questions in the forum. Also look into the manual & the mailing list archive. Prasenjit. PS: Don't forget to add ur affiliation.....its a netiquette for this forum. 2009/4/7 Dimpy Sharma <dimpy.sharma at tyndall.ie> > > Hi, > > Can anyone please explain me the significance of ecutwfc and ecutrho in > quantum espresso input file. And what is the diffeence between these two > values. > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- PRASENJIT GHOSH, POST-DOC, ROOM NO: 265, MAIN BUILDING, CM SECTION, ICTP, STRADA COSTERIA 11, TRIESTE, 34104, ITALY PHONE: +39 040 2240 369 (O) +39 3807528672 (M) -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20090407/4a3408ce/attachment.htm
