Index

Modulated structures dictionary (msCIF) version 3.2.1

_atom_site_U_Fourier_param.phase

Name:
_atom_site_U_Fourier_param.phase

Alias:
_atom_site_U_Fourier_param_phase

Definition:

   

      The modulation of the ADP is usually
      parameterized by Fourier series. Each term of the series
      commonly adopts two different representations: the sine-cosine
      form,
           U(ij)c cos(2\\p k r)+U(ij)s sin(2\\p k r),
      and the modulus-argument form,
           |U(ij)| cos(2\\p k r+\\c),
      where k is the wave vector of the term and r is the atomic
      average position. _atom_site_U_Fourier_param.phase is the phase
      (\c/2\\p), in cycles, of the complex amplitude corresponding to\
      the Fourier term defined by 
      _atom_site_U_Fourier.atom_site_label,
      _atom_site_U_Fourier.tens_elem and
      _atom_site_U_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_U_Fourier_param

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

Category:
atom_site_U_Fourier_param