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RE: [sdpd] hydrogen bonds distances
Hi,
I'd echo the comments of Armel. Without knowing
how good the data are, how far out the compounds
diffract, what constraints / restraints have
been applied and what weightings have been used, there's
not a lot that can be said with confidence.
There's also a wee bit of ambiguity
in your description of what you've done. You say
"use Powder Solve and Forcite software integrated in Materials
Studio to solve the structures combining Rietveld refinement and Energy
minimizations"
Do you mean that you've solved the structures and
then gone on to refine them with combined Rietveld /
Energy minimisation? Or that you've solved then
by combined Rietveld / energy minimisation...?
However, the O...O distance is presumably between
carboxylic acid grounps that are H-bonded across
a centre of symmetry and so if you are returning
distances in the range 2.5-2.7A, you are in pretty
good shape. A quick & dirty search of the CSD for
O...O distances in dimerised carboxylic acids gives
an average O...O distance of about 2.65A.
In the end analysis, it's only lab powder data
so you can't expect too much from it.
Sadly, you won't need to come to a neutron source
to get good O...O distances. If you suspect that
your H atoms are doing something interesting, then
that's a different story!
Cheers,
Kenneth
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