Sarah Price opened a general discussion of the paper by Sven Schroeder: I have been generating the thermodynamically plausible crystal structures of organic molecules for many years, and back in 2004 we did a crystal structure prediction (CSP) study on imidazole1 and found that it was relatively straightforward. Following your paper, we have reclassified the low energy structures according to the tilt within the hydrogen-bonded chain and the relative direction of the chains. Although the observed structure was the global minimum, two other structures with a displacement of otherwise identical layers are very close in energy. Do you think that if imidazole had crystallised in one of these alternative structures it would be distinguishable by NEXAFS? This would be a very sensitive test of whether NEXAFS combined with CSP could be used in characterising crystal structures.
- crystal structures
- organic molecules