Posts Tagged ‘energy difference’

Molecule orbitals as indicators of reactivity: bromoallene.

Thursday, September 1st, 2016

Bromoallene is a pretty simple molecule, with two non-equivalent double bonds. How might it react with an electrophile, say dimethyldioxirane (DMDO) to form an epoxide?[cite]10.1039/C6CC06395K[/cite] Here I explore the difference between two different and very simple approaches to predicting its reactivity. bromoallene

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Bond stretch isomerism. Did this idea first surface 100 years ago?

Tuesday, February 9th, 2016

The phenomenon of bond stretch isomerism, two isomers of a compound differing predominantly in just one bond length, is one of those chemical concepts that wax and occasionally wane.[cite]10.1016/S1631-0748(02)01380-2[/cite] Here I explore such isomerism for the elements Ge, Sn and Pb.

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Oxime formation from hydroxylamine and ketone: a (computational) reality check on stage one of the mechanism.

Sunday, September 23rd, 2012

The mechanism of forming an oxime from nucleophilic addition of a hydroxylamine to a ketone is taught early on in most courses of organic chemistry. Here I subject the first step of this reaction to form a tetrahedral intermediate to quantum mechanical scrutiny.

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Driving the smallest car ever made: a chemical perspective.

Thursday, November 10th, 2011

Fascination with nano-objects, molecules which resemble every day devices, is increasing. Thus the world’s smallest car has just been built[cite]10.1038/nature10587[/cite]. The mechanics of such a device can often be understood in terms of chemical concepts taught to most students. So I thought I would have a go at this one!

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