The more finely divided it is, the faster the hydration would occur.
Nice, facetted single crystals of Periclase tend to go a cloudy colour
after a while - which is most likely hydration to brucite occuring on
the surface.
This was going to be one of the phases in the Quantitative Phase Round Robin
Good, problem free standards are not easy to find.
-------
On the topic of standards, has a choice been made on a phase for the possible
2nd Rietveld refinement round robin? Chromium stabilized beta di calcium
silicate (larnite) is still my favourite option - double the complexity of
monoclinic zirconia.
Cheers,
Lachlan.
>Solution ??
>Why not using MgO, which has been measured against Si for precise unit
>cells. MgO might have slight broadening, which improves fitting with
>PseudoVoigt profiles. It is cubic and has at least three peaks with I >
>10%. Its mass attenuation is not too far away from our sample phases.
>
>Any objections against using this stuff? Have I overlooked something else
>to think about?
>
>Thanks in advance
>
>Helge Stanjek
>
>
>
>
>
Lachlan Cranswick - Melbourne, Australia _--_|\
Phone/Fax : (613) 9455-1345 / \
E-mail : lachlan@melbpc.org.au \_.--._/
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