Borrmann effect

The Borrmann effect (or Borrmann–Campbell effect after Gerhard Borrmann and Herbert N. Campbell) is the anomalous increase in the intensity of X-rays transmitted through a crystal when it is being set up for Bragg reflection.

The Borrmann effect—a dramatic increase in transparency to X-ray beams—is observed when X-rays satisfying Bragg's law diffract through a perfect crystal. The minimization of absorption seen in the Borrmann effect has been explained by noting that the electric field of the X-ray beam approaches zero amplitude at the crystal planes, thus avoiding the atoms.

References

{{cite journal |last1=Nasonov |first1=Nikolai N. |title=Borrmann effect in parametric X-ray radiation |journal=Physics Letters A |volume=260 |issue=5 |date=20 September 1999 |pages=391–394 |doi=10.1016/S0375-9601(99)00545-9 |publisher=Elsevier |bibcode=1999PhLA..260..391N }}
{{cite journal |last1=Pettifer |first1=Robert F. |first2=Stephen P. |last2=Collins |first3=David |last3=Laundy |year=2009 |title=Quadrupole transitions revealed by Borrmann spectroscopy |journal=Nature |volume=454 |issue=7201 |pages=196–199 |doi=10.1038/nature07099 |bibcode=2008Natur.454..196P |pmid=18615080|s2cid=4346649 }}
Borrmann, Gerhard; Über Extinktionsdiagramme von Quarz, Physikalische Zeitschrift 42, 157–162 (1941); [https://doi.org/10.1007%2FBF01329828 Die Absorption von Röntgenstrahlen im Fall der Interferenz, Zeitschrift für Physik 127, 297–323 (1950)] - original articles on Borrmann effect
Campbell, Herbert N.; [http://scitation.aip.org/content/aip/journal/jap/22/9/10.1063/1.1700122 X-Ray Absorption in a Crystal Set at the Bragg Angle], Journal of Applied Physics 22, 1139 (1951)
von Laue, Max; [http://scripts.iucr.org/cgi-bin/paper?S0365110X49000242 Die Absorption der Röntgenstrahlen in Kristallen im Interferenzfall, Acta Crystallographica 2, 106–113 (1949)] - original explanation of Borrmann effect

Category:X-ray crystallography