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_pd_instr

This section contains information relevant to the instrument used for the diffraction measurement, similar to this IUCr section.

_pd_instr.resolution

In general, the profile of a Bragg reflection centred at the peak position can be approximated by mathematical convolution of contributions from the instrument, called the instrumental resolution function, and from the microstructure of the sample. Because many contributions to powder diffraction peaks have a nearly Gaussian or Lorentzian shape, the pseudo-Voigt function, is widely used to describe peak profiles in powder diffraction.

Half-width parameters (normally characterising the instrumental resolution function) as implemented in CrysPy:

  • _pd_instr.resolution_u
  • _pd_instr.resolution_v
  • _pd_instr.resolution_w

Lorentzian isotropic microstrain parameter as implemented in CrysPy:

  • _pd_instr.resolution_x

Lorentzian isotropic particle size parameteras implemented in CrysPy:

  • _pd_instr.resolution_y

_pd_instr.reflex_asymmetry

Peak profile asymmetry parameters as implemented in CrysPy.

  • _pd_instr.reflex_asymmetry_p1
  • _pd_instr.reflex_asymmetry_p2
  • _pd_instr.reflex_asymmetry_p3
  • _pd_instr.reflex_asymmetry_p4

_pd_instr.2theta_bank

Time-of-flight parameters as implemented in CrysPy.

_pd_instr.dtt

Time-of-flight parameters as implemented in CrysPy.

  • _pd_instr.dtt1
  • _pd_instr.dtt2

_pd_instr.zero

Time-of-flight parameters as implemented in CrysPy.

_pd_instr.alpha

Time-of-flight parameters as implemented in CrysPy.

  • _pd_instr.alpha0
  • _pd_instr.alpha1

_pd_instr.beta

Time-of-flight parameters as implemented in CrysPy.

  • _pd_instr.beta0
  • _pd_instr.beta1

_pd_instr.sigma

Time-of-flight parameters as implemented in CrysPy.

  • _pd_instr.sigma0
  • _pd_instr.sigma1
  • _pd_instr.sigma2