>And the question is really : if I do not succeed at home, can I really
>succeed on a big instrument ? I think yes if those numbers mean
>really something. Hence the need to define what they mean.
And the last numbers are, in 'equivalent conventional X-ray at 1.54A
units' of FWHM, which really means something :
minimal FWHM (�2th) Where ?
Neutron constant wavelength 0.12 NIST
Conventional X-ray 0.04 >5000 places in the world
Neutron ToF 0.03 HRPD
ISIS
Synchrotron X-ray <0.01 ESRF and ?
corresponding to powder patterns that we really have 'touched
with our fingers'. You may translate in (delta d)/d if you want.
Any new value and place welcome. Remember where this (stupid?)
comparison takes place, before to explode : SDPD (Structure
Determination by Powder Diffractometry), not at all for magnetism,
tunability of wavelength and so on, only SDPD for which resolution
counts, first for indexing, then for extracting structure factors used
for solving, and finally for refining by the Rietveld method : this
whole process being called "(ab initio) structure determination".
Best,
Armel
