plane waves form an orthonormal basis set. whether this defines a generalized eigenvalue problem or not depends on what you use planewaves for. If they expand the full vawefunction (as in norm-conserving PP) you have a normal eigenvalue problem , if you expand the pseudo part of a wfc that needs to be augmented to reconstruct the charge density (USPP or PAW) a generalized eigenvalue problem results.
stefano On 10/03/2012 01:00 PM, Padmaja Patnaik wrote: > Hi All > > I have a query. Anybody please can explain this.If you use the plane wave > basis, will you have generalized eigenvalue problem? > > > Padmaja Patnaik > Research Scholar > Dept of Physics > IIT Bombay > Mumbai, India > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20121003/45918301/attachment.html