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Discussion: Comparison |
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Discussion: Comparison
Once the refined structure of the compound has been described, the
remaining part of the discussion section should concern the validity of
that structure.
The main points that need to be covered are as follows:
- A comparison of the geometrical parameters that you are presenting with
those
already reported in the literature or structural databases (see subsequent
sections) for compounds with similar structural features to yours. For example,
if you have a structure containing PO4 tetrahedra
then you should compare the P-O bond distances and O-P-O bond angles with
those found for other structures containing this unit in a similar structural
environment.
- A discussion of the significance of the geometrical and structural
parameters that you are using relative to the errors on them. It is difficult
to provide a credible chemical argument on the basis of a refined parameter
whose value is not greater than its error.
- A discussion of any unusual results you are presenting (in the tables or
pictures) that need to be clarified, many of which have been mentioned in
previous sections. Some examples of unusual results are short or long bond
lengths, site occupancies that are > 1 or < 1, and temperature factors that
are particularly high.
- A broader discussion of how the structure you are describing fits in with
other families of related structures, such as any related minerals or
natural products with similar structures. The content of this section
depends very much on your reasons for pursuing your research.
Interpretation
As stated in other sections, carefully read this section in an article and make
sure it is consistent with the refined parameters, and their values, that are
presented within the tables of structural, atomic and geometrical parameters.
Check the appropriateness of the structures that the authors have selected
from the literature for use to validate the geometrical parameters they have
obtained in their refinement. If the discussion does not have a comparison to
other known structures then something may be seriously wrong and you should
carefully scrutinise the results they are presenting.
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