Hi Stefano, The front page for the QE wiki is edit protected. I think it would be useful to add a link from there to Documentation. Once someone puts that in place, I would be glad to put up some of the INPUT_* files on the Documentation wiki page.
Regards, Derek Stefano Baroni writes: > Thank you Edoardo. > Your correspondence demonstrates that it is high time to move the > documentation to the wiki. > Are you (or any of your collaborators, or any of the subscribers to this > mailing list) willing to help? > Stefano > > On Feb 7, 2007, at 1:46 PM, Eduardo Ariel Menendez P wrote: > >> >> Thanks Stefano for the clariying this issue. I have a humble suggestion >> for the documentation (INPUT_PW), which is just a feedback from my own >> doubts and time spent thinking and testing. >> >> This is a section of INPUT_PW >> >> delta_t REAL ( default = 1.D0 ) >> delta_t = 1 : every 'nraise' step the >> actual >> temperature is rescaled to >> tempw >> delta_t /= 1 && delta_T > 0 : at each step the >> temperature is >> multiplied by delta_t; this >> is >> done rescaling all the >> velocities. >> delta_t < 0 : every 'nraise' steps >> temperature >> is reduced by -delta_T >> This keyword is NOT used in the case of variable cell >> calculations. >> >> This is the way that would be instantly clear to my twin brother or my >> clon, with a few more bytes of disk space. >> >> delta_t REAL ( default = 1.D0 ) >> delta_t = 1 : every 'nraise' step the >> instantaneous >> temperature is rescaled to >> tempw >> delta_t /= 1 && delta_T > 0 : at each step the >> instantaneous temperature is >> multiplied by delta_t; this >> is >> done rescaling all the >> velocities. See comment >> below. >> delta_t < 0 : every 'nraise' steps the >> instantaneous temperature >> is reduced by - delta_T. See >> comment below. >> This keyword is NOT used in the case of variable cell >> calculations. >> The instantaneous temperature is calculated at the end of >> every >> ionic move and BEFORE rescaling. This is the temperature >> reported >> in the main output. >> For delta_t /= 1, the actual average rate of heating or >> cooling >> should be rougly C*delta_t/(nraise*dt) (C=1 for an >> ideal gas, C=0.5 for a harmonic solid, theorem of energy >> equipartition between all quadratic degrees of freedom). >> >> Regards >> Eduardo >>>> > > ... > >>>> 1) IS there somthing wrong in this setting? >>>> 2) Is the net temperature rescaling equal to delta_t*nstep/ nraise, or >>>> this >>>> is only an estimate? >>>> 3) It seems that I must either scale longer time or increase delta_t. >>>> Is >>>> there any other option? >>>> >>>> Thanks >>>> Eduardo >>>> _______________________________________________ >> k >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://www.democritos.it/mailman/listinfo/pw_forum > > --- > Stefano Baroni - SISSA & DEMOCRITOS National Simulation Center - > Trieste > [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype) > > Please, if possible, don't send me MS Word or PowerPoint attachments > Why? See: http://www.gnu.org/philosophy/no-word-attachments.html > > > ################################ Derek Stewart, Ph. D. Scientific Computation Associate 250 Duffield Hall Cornell Nanoscale Facility (CNF) Ithaca, NY 14853 stewart (at) cnf.cornell.edu (607) 255-2856
