**Definition:**

_atom_site_occ_special_func_crenel_ items are the adjustable parameters of a crenel function. An occupational crenel function along the internal space is defined as follows: p(x4)=1 if x4 belongs to the interval [c-w/2,c+w/2] p(x4)=0 if x4 is outside the interval [c-w/2,c+w/2], where x4 is the internal coordinate, c is the centre of the function in internal space and w is its width. The use of this function is restricted to one-dimensional modulated structures. For more details, see the manual for JANA2000 (Petricek & Dusek, 2000). Reference: Petricek, V. & Dusek, M. (2000). JANA2000. The crystallographic computing system. Institute of Physics, Prague, Czech Republic.

Appears in list containing _atom_site_occ_special_func_atom_site_label

Enumeration default: 0.0

**Type:** numb

**Category:** atom_site_occ_special_func

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