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Modulated structures dictionary (msCIF) version 3.2.1
_atom_site_occ_Fourier_param.modulus
Name:_atom_site_occ_Fourier_param.modulus
Alias:
_atom_site_occ_Fourier_param_modulus
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_modulus is the modulus (|P|) of the complex amplitude 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
The permitted range is 0.0 → infinity
Enumeration default: 0.0
Evaluation method:
With p as atom_site_occ_Fourier_param atom_site_occ_Fourier_param.modulus = Sqrt(p.cos**2+p.sin**2)
Category:
atom_site_occ_Fourier_param