Index

Modulated structures dictionary (msCIF) version 3.2.1

_atom_site_occ_Fourier_param.phase

Name:
_atom_site_occ_Fourier_param.phase

Alias:
_atom_site_occ_Fourier_param_phase

Definition:

   

      The occupational distortion of a given atom or rigid group is
      usually parameterized by Fourier series. Each term of the series
      commonly adopts two different representations: the sine-cosine
      form,
           Pc cos(2\\p k r)+Ps sin(2\\p k r),
      and the modulus-argument form,
           |P| cos(2\\p k r+\\d),
      where k is the wave vector of the term and r is the atomic
      average position. _atom_site_occ_Fourier_param.phase is the phase
      (\d/2\\p) in cycles corresponding to the Fourier term defined by\
      _atom_site_occ_Fourier.atom_site_label and
      _atom_site_occ_Fourier.wave_vector_seq_id.

Type: Real

Units: cycles

The permitted range is -1.0 → 1.0

Enumeration default: 0.0

Evaluation method:

      With  p  as  atom_site_occ_Fourier_param

       atom_site_occ_Fourier_param.phase =  Phase(Complex(p.cos,-p.sin))/TwoPi

Category:
atom_site_occ_Fourier_param