Angle-dependent X-ray absorption correction in small- and wide-angle X-ray scattering : accounting for constrained scattering volume, beam profiles and capillary wall attenuation

Kovač, Jure (avtor), Jamnik, Andrej (avtor), Szilágyi, István (avtor), Tomšič, Matija (avtor)

A GPU-accelerated numerical method has been developed to calculate angle-dependent transmission factors A(2θ) for small- and wide-angle X-ray scattering (SWAXS) data collected with a Kratky-type camera using a line-collimated beam and a horizontal cylindrical capillary with a vertically oriented detector. The procedure extends path-length-based absorption correction to the Kratky-type geometry by averaging Beer–Lambert attenuation over the constrained illuminated scattering volume and by including experimentally measured primary beam profiles and capillary-wall absorption. Sensitivity analysis shows that the vertical illumination geometry dominates the calculated angle-dependent transmission factor, whereas the horizontal beam-width effect is negligible. Using measured beam profiles makes the correction instrument specific and avoids introducing an effective uniform beam height as an approximation. For strongly absorbing nona­fluoro-tert-butanol, the conventional scalar primary beam transmission correction fails after subtraction of empty-capillary scattering, while the numerical correction enables physically meaningful absolute-scale data reduction. Comparisons between independently calculated theoretical SWAXS intensities and the two reduced experimental datasets obtained sequentially using two different detectors in the same experiment on the same Kratky-type SWAXS camera provide a direct experimental cross check for the data-reduction workflow based on calculated transmission factors. They indicate that the observed limitation is associated with transmission measurement of a spectrally modified primary beam, rather than with the Kratky-type geometry itself. Importantly, the results show that the limitations of conventional scalar transmission corrections are not confined to extreme cases but may also affect routine water-based absolute-scale SWAXS calibration. A simple Beer–Lambert-type numerical scalar correction can still provide a useful qualitative approximation, whereas reliable quantitative analysis requires the full angle-dependent A(2θ) correction.

• Jezik: Angleški jezik
• Ključne besede: transmission correction coefficients, X-ray absorption correction, fluorinated liquids, Kratky cameras, absolute scaling, wide-angle X-ray scattering, WAXS, small-angle X-ray scattering, SAXS, SWAXS, perfluorinated alkyl substances, PFAS
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2026
• Št. strani: 10 str.
• Številčenje: Vol. 59, no. 5
• PID: 20.500.12556/RUL-188118
• UDK: 544.27
• ISSN pri članku: 1600-5767
• DOI: 10.1107/S1600576726006837
• COBISS.SI-ID: 288280579
• Datum objave v RUL: 18.09.2026

Gradivo je del revije

• Naslov: Journal of applied crystallography
• Skrajšan naslov: J. appl. crystallogr.
• Založnik: Blackwell
• ISSN: 1600-5767
• COBISS.SI-ID: 22700071

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: koeficienti transmisijske korekcije, korekcija absorpcije rentgenskih žarkov, fluorirane tekočine, Kratkyjeve kamere, absolutno skaliranje, širokokotno sipanje rentgenskih žarkov, WAXS, malokotno sipanje rentgenskih žarkov, SAXS, SWAXS, perfluorirane alkilne snovi, PFAS