[CPMD-list] About the periodic boundary condition

[Axel Kohlmeyer]

On Tue, 17 Apr 2007, liu liuxiandong wrote:

XL> Dear CPMD users,

dear xiandong,

XL> In the ATOM section, can the input coordiantes exceed the box dimension ?
XL> For example, in a cubic box (10*10*10), a hydroxyl (-OH ) group has the
XL> coordinates: Oxygen (0, 0, 9.5) and Hydrogen (0, 0, 10.5). Should I input
XL> these coordinates or, Oxygen (0, 0 , 9.5) and Hydrogen (0, 0, 0.5) ? how
XL> CPMD treats this  ?

cpmd internally always folds coordinates back into the primary 
supercell, but preserves their 'normal' positions in the output.
so both sets of coordinates should get the same result, but the
first will look better in visualization.

cheers,
  axel.

XL> Thanks.
XL> 
XL> BEST
XL> 
XL> XIANDONG
XL> 

-- 
=======================================================================
Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
   Center for Molecular Modeling   --   University of Pennsylvania
Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
tel: 1-215-898-1582,  fax: 1-215-573-6233,  office-tel: 1-215-898-5425
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