Currently it is not possible to provide atomic velocities from input in pw.x. It can be done with the Car-Parrinello code.
Velocities are not used in the Verlet algorithm implemented in pw.x. They have to be computed from positions as (x(t+dt)-x(t-dt))/(2dt) Paolo On Mon, Oct 19, 2015 at 6:16 PM, Venkataramana Imandi < venkataramana.ima...@gmail.com> wrote: > > Dear QE users, > > I checked entire manual and keywords list of pw.x, there is nowhere > information about manual entering of atomic velocities in the input file, > If necessary sometimes. Moreover, I have seen dynamics_module.f90 file, it > is shown that velocities are initialized from Maxwell-Boltzmann > distribution or random number distribution or zero velocities. So, please > make me understand, > how to give manually velocities at a particular time step. In the input > file, I am giving atomic coordinates in the angstrom units. If there is an > option to give velocities in the input file, please > tell me keywords information and what type of units I have to give for > velocities (e.g. angstroms/rydberg, Bohrs/rydberg). > > In addition, in the output file, there is only updated atomic coordinates > and no updated velocities at each time step. Can you please give a comment > of the bit of code along with where to insert those bit of code in the > dynamics_module.f90 file or wherever in the code, by that I can improve to > add or doing something on the code to print updated velocities at each time > step. Please, any suggestions are necessary to me. I don't have much > command on the code, at-least I can try my level best. > > I anticipated thanks for suitable answers from well-wishers. > > > venkataramana > PhD student > IIT Bombay > > _______________________________________________ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Paolo Giannozzi, Dept. Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
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