Posts Tagged ‘search software’

π-Facial hydrogen bonds to alkenes (revisited): how close can an acidic hydrogen approach?

Saturday, April 15th, 2017

Back in the early 1990s, we first discovered the delights of searching crystal structures for unusual bonding features.[cite]10.1039/P29940000703[/cite] One of the first cases was a search for hydrogen bonds formed to the π-faces of alkenes and alkynes. In those days the CSD database of crystal structures was a lot smaller (<80,000 structures; it’s now ten times larger) and the search software less powerful. So here is an update. 

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Molecules of the year? Pnictogen chains and 16 coordinate Cs.

Monday, December 19th, 2016

I am completing my survey of the vote for molecule of the year candidates, which this year seems focused on chemical records of one type or another.

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Deviations from tetrahedral four-coordinate carbon: a statistical exploration.

Sunday, September 6th, 2015

An article entitled "Four Decades of the Chemistry of Planar Hypercoordinate Compounds"[cite]10.1002/anie.201410407[/cite] was recently reviewed by Steve Bacharach on his blog, where you can also see comments. Given the recent crystallographic themes here, I thought I might try a search of the CSD (Cambridge structure database) to see whether anything interesting might emerge for tetracoordinate carbon.

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