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Twinning dictionary version 1.0





   Calculated value for the overall squared structure factors (in
   electrons squared for X-ray diffraction) arising from all 
   the twin contributions to the peak defined by _twin_refln_datum_id.  
   The total contribution from all twins to a single observed
   reflection is modelled according to the method of Pratt, Coyle
   and Ibers as follows:

   _twin_refln_F_squared_calc = osf * Sum (mf * _refln_F_squared_calc)

   where osf is the overall scale factor,
   mf is the mass fraction,
   and the sum is taken over all the twin components that contribute
   to this diffraction peak.

   Reference: Pratt, C. S., Coyle, B. A. & Ibers, J. A. (1971).
   J. Chem. Soc. A, pp. 2146-2151.

Appears in list containing _twin_refln_datum_id   _twin_refln_individual_id

Type: numb

Category: twin_refln