-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dear Pietro,
You may take a textbook into account which deals with Laue diffraction. If you search for the keyword "Laue" and the author "Helliwell" at the IUCR journals, you will get a large number of hits, indicating that this is by no means a 'trivial' issue (e.g. http://dx.doi.org/10.1107/S0909049599006366 for an overview or http://dx.doi.org/10.1107/S0108767387098763 for the treatment of harmonics). As far as I understand, certain scaling programs take the lambda/2 contribution of monochromators into account. Regards, Tim Gruene On 08/20/2013 04:36 PM, Pietro Roversi wrote: > Dear all, > > I am shocked by my own ignorance, and you feel free to do the same, > but do you agree with me that according to Bragg's Law a > diffraction maximum at an angle theta has contributions to its > intensity from planes at a spacing d for order 1, planes of spacing > 2*d for order n=2, etc. etc.? > > In other words as the diffraction angle is a function of n/d: > > theta=arcsin(lambda/2 * n/d) > > several indices are associated with diffraction at the same angle? > > (I guess one could also prove the same result by a number of Ewald > constructions using Ewald spheres of radius (1/n*lambda with > n=1,2,3 ...) > > All textbooks I know on the argument neglect to mention this and in > fact only n=1 is ever considered. > > Does anybody know a book where this trivial issue is discussed? > > Thanks! > > Ciao > > Pietro > > > > Sent from my Desktop > > Dr. Pietro Roversi Oxford University Biochemistry Department - > Glycobiology Division South Parks Road Oxford OX1 3QU England - UK > Tel. 0044 1865 275339 - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFSE4EgUxlJ7aRr7hoRAomhAJ94WrXRCTx8gevMAzrhenVri2EkhwCghyC1 UuckhqtUEG0uB9hheG1uxz0= =+cAo -----END PGP SIGNATURE-----
