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Re: Phase ID draft report

Dear Sidney,

Thanks for your careful reading of the proposed report on the phase 
identifier. I will incorporate your comments in the next draft. I only 
want to comment here on one item to clear up a misunderstanding.

> 7. In “6.3 Layer 7. Wyckoff Sequence”
>
> It would be more appropriate here to use the same Wyckoff site order 
> as used in ITA, i.e. number, followed by letter. It would also be 
> helpful if the example contained at least two sites with multiplicity 
> other than 1, so that it becomes, for example, ‘1a 2c 3f 6g’ or 
> ‘a2c3f6g’, to avoid possible confusion with the dropped ‘1’ (which I 
> agree should be dropped).
>
There is a confusion between the multiplicty of the Wyckoff position and 
the number of symmetry-independent atoms that occupy the position. In 
the example given (adi6), a and d presumably have different 
multiplicities, say 1 and 4, but these are not shown. i is likely to be 
a general position with, say, multiplicity 8. The multiplicities are not 
shown as they can be found in ITA since the space group number is known, 
but the total number of atoms in the cell in this example would be 1x1 + 
1x4 + 6x8 = 53. This point clearly needs to be made clearer and I will 
do this in the next version.

David


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