There is a tutorial on the CPDW webpage at http://www.cins.ca/cpdw/notes.html on using annealed cubic Y2O3 to determining polarisation via GSAS.
It is cubic and has a good peak density over the range of 2-theta. Y2O3 gives a stable and robust refinement result for polarisation . Lachlan >Hi, > >I am going to be in the same boat soon, especially regarding obtaining >instrument parameters for a new instrument. But one thing I do know, is that >to get the polarization parameter, quartz is not a great standard. For >polarization factors, you need something really simple, with heavy atoms and >all atoms on centers of symmetry, and with thermal parameters very well >constrained, so that you can REFINE the polarization parameters for your >machine, particularly when incindent beam monochromators are used. > >The only problem is, I can't remember what the favorite standard is, or where >it can be purchased. I will need to know myself, so I will ask, on behalf of >Blaise and myself as well, what is the best standard for refining the >polarization of an instrument with monochromatized beam? Thank you! > >- Kurt > ----------------------- Lachlan M. D. Cranswick Contact outside working hours / Coordonnees en dehors des heures de travail: NEW E-mail / courriel: lachlanc *at* magma.ca Home Tel: (613) 584-4226 ; Cell/mobile: (613) 401-6254 WWW: http://lachlan.bluehaze.com.au/ P.O. Box 2057, Deep River, Ontario, Canada, K0J 1P0 (please use clear titles in any Email - otherwise messages might accidentally get put in the SPAM list due to large amount of junk Email being received. If you don't get an expected reply to any messages, please try again.) (Essayez d'utiliser des titres explicites - sans quoi vos messages pourraient aboutir dans un dossier de rebuts, du fait de la quantite tres importante de pourriels recue. Si vous n'obtenez pas la reponse attendue, merci de bien vouloir renvoyer un message.)
