Archive for March, 2018
Sunday, March 18th, 2018
Around the time of the 2012 olympic games, the main site for which was Stratford in east London, I heard a fascinating talk about the “remediation” of the site from the pollution caused by its industrial chemical heritage. Here I visit another, arguably much more famous and indeed older industrial site.
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Tags:City: London, Environment, Environmental Issues, Environmental toxicology, Geography of London, industrial chemical heritage, industrial site, Interesting chemistry, London Borough of Newham, London boroughs, Pollution, Province/State: Swansea, Queen Elizabeth Olympic Park, river Tawe, Stratford, Stratford London, Stratford station, Summer Olympics, the 2012 olympic games, unfortunate by-product, William Blake
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Sunday, March 18th, 2018
I have posted often on the chemical phenomenon known as hypervalency, being careful to state that as defined it applies just to “octet excess” in main group elements. But what about the next valence shell, occurring in transition metals and known as the “18-electron rule”? You rarely hear the term hypervalency being applied to such molecules, defined presumably by the 18-electron valence shell count being exceeded. So the following molecule (drawn in three possible valence bond representations) first made in 1992 intrigues.[1]
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References
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R. Ahlrichs, D. Fenske, H. Oesen, and U. Schneider, "Synthesis and Structure of [Ni(PtBu6)] and [Ni5(PtBu)6(CO)5] and Calculations on the Electronic Structure of [Ni(PtBu)6] and (PR)6, R = tBu,Me", Angewandte Chemie International Edition in English, vol. 31, pp. 323-326, 1992. http://dx.doi.org/10.1002/anie.199203231
Tags:Hypervalency
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Wednesday, March 7th, 2018
C&EN has again run a vote for the 2017 Molecules of the year. Here I take a look not just at these molecules, but at how FAIR (Findable, Accessible, Interoperable and Reusable) the data associated with these molecules actually is.
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Tags:Carotenoids, Chemical IT, Chemistry, Epoxides, Interesting chemistry, Macrocycles, Organic chemistry, Organofluorides, PDF, Peptides, search engine, search program, search.datacite.org search engine, Technology/Internet
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Sunday, March 4th, 2018
A bond index (BI) approximately measures the totals of the bond orders at any given atom in a molecule. Here I ponder what the maximum values might be for elements with filled valence shells.
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Tags:Atom, Chemical bond, chemical bonding, chemical properties, Chemistry, Interesting chemistry, metal bond indices, Molecule, Nature, Quantum chemistry, Residential REITs, Resonance, Tennessine, Valence, Valence electron
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