siva rama krishna wrote: > Dear Users, > > Could anyone please let me know how to write a new constraint on the > centre of mass of a molecule. > I want to allow an approaching molecule onto a substrate to move along > XY plane while its Z-component of centre of mass is arrested. > One can arrest the Z-component of an atom by setting ' > if_pos(nat)(3)=0 ' for the atom with index number 'nat'. > Similarly, can we arrest the Z-component of the centre of mass of a > molecule ? Yes, you can. By put "if_pos(nat)(3) = 0" for all atoms in the molecule the Z-component of the center of mass of the molecule will be unchanged
Linh > > Thanks and Regards, > > Sivaramakrishna J > Member of Technical Staff > Computational Research Labs, Pune. > India > ------------------------------------------------------------------------ > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -- ----------------------------------------------------- Nguyen Ngoc Linh, PhD Student c/o: SISSA & CNR-INFM Democritos, via Beirut 2-4, 34014 Trieste (Italy) email: nnlinh at sissa.it phone: +39 04 03787 319 skype: ngoclinh84phys ----------------------------------------------------- "The physics is theoretical but the fun is real"
