TY - JOUR A1 - Wuttke, Joachim T1 - Numerically stable form factor of any polygon and polyhedron Y1 - 2021-03-25 VL - 54 IS - 2 SP - 580 EP - 587 JF - Journal of Applied Crystallography DO - 10.23689/fidgeo-4286 PB - International Union of Crystallography N2 - Coordinate‐free expressions for the form factors of arbitrary polygons and polyhedra are derived using the divergence theorem and Stokes's theorem. Apparent singularities, all removable, are discussed in detail. Cancellation near the singularities causes a loss of precision that can be avoided by using series expansions. An important application domain is small‐angle scattering by nanocrystals. N2 - Coordinate‐free expressions for the form factors of arbitrary polygons and polyhedra are derived using the divergence theorem and Stokes's theorem. Series expansions are used to ensure numeric precision close to apparent singularities. image UR - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8632 ER -