Dear Lihui, oulihui666 wrote: > Dear Gabriele Sclauzero, > I am intend to calculate the frequency of CO2 molecule, so I should > perform scf calculation at first, when setting k points as gamma, it > will appear a error in the process of calculating frequency, as follows: > *********************************************************************** > from phq_readin. error #1 > cannot start from pw.x data file using Gamma-point tricks > ***********************************************************************
From what I can understand, this does not mean that you cannot do the calculation for the Gamma point only, but rather that the calculation cannot be done using Gamma point-specific algorithms (which are much faster than the general ones). You should anyway be allowed to do the calculation using K_POINTS AUTOMATIC 1 1 1 0 0 0 which builds a k-point grid containing the Gamma point only, but does not use Gamma-point tricks. You can do the relaxations (and all other expensive pw calculations) using K_POINTS GAMMA and then, starting from the optimized atomic positions, do a nscf run using K_POINTS AUTOMATIC 1 1 1 0 0 0 before the phonon run. Cheers GS P.S: please avoid private mails and stick to the thread you started in the forum, so that anyone can help and know when your problem has been solved. Thanks! > So I do not set k point as gamma in scf calculation. > > Best regards > Lihui > > -- > ====================================== > Lihui Ou > PH.D Candidate in Electrochemistry > College of Chemistry and Molecular Science > Wuhan University,/430072/,Hubei Province,China > /E-mail:oulihui666 at 126.com <mailto:oulihui666 at 126.com>/ > ====================================== > > > ------------------------------------------------------------------------ > ???????????,www.yeah.net <http://www.yeah.net/?from=footer> -- o ------------------------------------------------ o | Gabriele Sclauzero, PhD Student | | c/o: SISSA & CNR-INFM Democritos, | | via Beirut 2-4, 34014 Trieste (Italy) | | email: sclauzer at sissa.it | | phone: +39 040 3787 511 | | skype: gurlonotturno | o ------------------------------------------------ o
