In Crystal Structure Prediction of organic molecular crystals, almost no prior information is used. Usually, only a rough accounting of space group prior probability is included by preferentially sampling the most common space groups, but even this is done to save computer time, not because it is considered a scientifically sound thing to do!
Sometimes CSD database frequencies of nearest neighbor interactions or hydrogen bonding motifs are used to score crystal structures, but this seems to be applied in an ad hoc manner, without mathematical rigor. In the latest blind test only scoring functions based on energy was used.
Why don't we consider prior probabilities of crystal structure properties, and perform the CSP as a Bayesian update? The scoring function would then be a probability evaluated by Bayes' theorem, the probability of observing a predicted structure is the prior probability times the evidence provided by the crystal structure prediction. An obvious advantage of this method is that it captures kinetic effects during nucleation and growth.
Hej Jonas!
Statistical approaches are used a lot in protein structure predictions, so its strange that its not used by you solid state guys? You should get it sorted! :) Might be worth looking up some papers on integrative structural biology?
Here is a paper where Bayes theorem is used. Instead of, 'blindly', searching for a structure with a good score (from homologies or other related structures, which is the most common approach) it actually uses known crystal and NMR data (that is incomplete but still has some information) to create a statistically sound ensemble. Might be related to what you are asking?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4460504/
Will be cool to see what other people have to say about this!
All the best
Thanks, Tee. That paper is an excellent introduction and example of what I want to do.
We should use statistics from large databases of crystals to create a prior probability distribution. This could include things like how common different space groups are, favorable and unfavorable close contacts and density (since crystals tend to be close-packed).
We then perform a CSP calculation and obtain a set of crystals, ranked by energy. Combining the prior probability with the new energy-based evidence with Bayes' theorem should give a better scoring.
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