Archive for January, 2019

The Chemistry of the Book of Kells

Tuesday, January 22nd, 2019
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The Book of Kells is a spectacularly illuminated gospel manuscript dating from around 800AD and held in Trinity College library in Dublin. Some idea of the colours achieved can be seen below. 

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Free energy relationships and their linearity: a test example.

Sunday, January 13th, 2019
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Linear free energy relationships (LFER) are associated with the dawn of physical organic chemistry in the late 1930s and its objectives in understanding chemical reactivity as measured by reaction rates and equilibria.

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Dispersion-induced triplet aromatisation?

Thursday, January 3rd, 2019
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There is emerging interest in cyclic conjugated molecules that happen to have triplet spin states and which might be expected to follow a 4n rule for aromaticity.[1] The simplest such system would be the triplet state of cyclobutadiene, for which a non or anti-aromatic singlet state is always found to be lower in energy. Here I explore some crystal structures containing this motif for possible insights.

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References

  1. A. Kostenko, B. Tumanskii, Y. Kobayashi, M. Nakamoto, A. Sekiguchi, and Y. Apeloig, "Spectroscopic Observation of the Triplet Diradical State of a Cyclobutadiene", Angewandte Chemie International Edition, vol. 56, pp. 10183-10187, 2017. http://dx.doi.org/10.1002/anie.201705228