Xray source width (w_{x}) 
Angle subtended by source: w_{x}/R 
Symmetric broadening 
Receivingslit width or PSD strip width (w_{r}) 
Angle subtended by slit/strip: w_{r}/R 
Symmetric broadening 
Flat specimen error/equatorial divergence 
Angle of divergence slit: α 
Asymmetric broadening to low 2θ, with decreasing 2θ 
PSD defocusing 
PSD window width, angle of divergence slit: α 
Symmetric broadening with 1/(tan θ) 
Axial divergence 

Below ∼ 100°: 
Case 1: no Soller slits 
Axial lengths of the Xray source (L_{x}), sample (L_{s}) and receiving slit (L_{r}) relative to goniometer radius (R) 
asymmetric broadening to low 2θ, with decreasing 2θ 
Case 2: Soller slits define divergence angle 
Acceptance angles Δ_{I} and Δ_{D} of the incident and diffractedbeam Soller slits 
else to high 2θ, with increasing 2θ 
Specimen transparency 
Penetration factor relative to diffractometer radius 1/μR 
Asymmetric broadening to low 2θ, with sin(2θ) 
Specimen displacement z height 
Displacement of specimen surface from goniometer rotation axes 
Displacement of profiles with cos θ 