Modulated Structures CIF Dictionary version 1.0

_atom_site_displace_special_func_sawtooth_

Names

Category: atom_site_displace_special_func

Data type: numb (with optional s.u. in parentheses)

Must appear in a looped list containing '_atom_site_displace_special_func_atom_site_label'
Enumeration default: 0.0

Definition

    	
    _atom_site_displace_special_func_sawtooth_ items are the 
    adjustable parameters of a sawtooth function. 
    
    A displacive sawtooth function along the internal space is 
    defined as follows:

                      ux=2*ax[(x4-c)/w]
                      uy=2*ay[(x4-c)/w]
                      uz=2*az[(x4-c)/w]

    where ax, ay and az are the amplitudes (maximum displacements) 
    along each crystallographic axis, w is its width, x4 is the 
    internal coordinate and c the center of the function in internal
    space. ux, uy and uz must be expressed in relative units. Its
    usage is restricted to one-dimensional modulated structures. For
    more details see for example the manual of JANA2000 (Petricek & 
    Dusek, 2000).