Hi Bernhard, On Wed, Oct 13, 2010 at 08:07:04PM -0700, Bernhard Rupp wrote: [...] > BR > > PS: Just in case it might come up - there is NO destructive interference > between F000 and direct beam - the required coherence that leads to > extinction/summation of 'partial waves' is limited to a single photon. > Standard (non-FEL) X-ray sources are (with minor exceptions in special > situations) not coherent. Has been discussed many times on bb. This sounds as though you are saying that a single photon interacts with several electrons to give rise to a reflection. If I understand Feynman diagrams correctly, this does not conform with current notion of photons. If your statement refers to a chapter in your book, please point that out before we discuss this on the bb so that I can set myself right.
Cheers, Tim -- -- Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen phone: +49 (0)551 39 22149 GPG Key ID = A46BEE1A
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