Harnessing FAIR data: A suggested useful persistent identifier (PID) for quantum chemical calculations.

August 7th, 2018

Harnessing FAIR data is an event being held in London on September 3rd; no doubt all the speakers will espouse its virtues and speculate about how to realize its potential. Admirable aspirations indeed. Capturing hearts and minds also needs lots of real life applications! Whilst assembling a forthcoming post on this blog, I realized I might have one nice application which also pushes the envelope a bit further, in a manner that I describe below.

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A Theoretical Method for Distinguishing X‐H Bond Activation Mechanisms.

July 25th, 2018

Consider the four reactions. The first two are taught in introductory organic chemistry as (a) a proton transfer, often abbreviated PT, from X to B (a base) and (b) a hydride transfer from X to A (an acid). The third example is taught as a hydrogen atom transfer or HAT from X to (in this example) O. Recently an article has appeared[cite]10.1002/anie.201805511[/cite] citing an example of a fourth fundamental type (d), which is given the acronym cPCET which I will expand later. Here I explore this last type a bit further, in the context that X-H bond activations are currently a very active area of research.

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FAIR Data in Amsterdam – FAIR data points.

July 18th, 2018

FAIR is one of those acronyms that spreads rapidly, acquires a life of its own and can mean many things to different groups. A two-day event has just been held in Amsterdam to bring some of those groups from the chemical sciences together to better understand FAIR. Here I note a few items that caught my attention.

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Chemistry (and music) in the Park.

July 12th, 2018

This last month, as a follow-up to the preceding post on the colour of flowers, I have been moonlighting by blogging elsewhere. Do go visit my “guerrilla blog” at perivalepark.london. Part of this project involves visiting two “physic or botanic” gardens, which originate from early 17th century explorations of herbs and other botanicals as medicines. Both are very old and their chemistry is indeed fascinating; more of which later.

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Why do flowers such as roses, peonies, dahlias, delphiniums (etc), exhibit so many shades of colours?

June 18th, 2018

It was about a year ago that I came across a profusion of colour in my local Park. Although colour in fact was the topic that sparked my interest in chemistry many years ago (the fantastic reds produced by diazocoupling reactions), I had never really tracked down the origin of colours in many flowers. It is of course a vast field. Here I take a look at just one class of molecule responsible for many flower colours, anthocyanidin, this being the sugar-free counterpart of the anthocyanins found in nature.

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Ten years on: Jmol and WordPress.

May 16th, 2018

Ten years are a long time when it comes to (recent) technologies. The first post on this blog was on the topic of how to present chemistry with three intact dimensions. I had in mind molecular models, molecular isosurfaces and molecular vibrations (arguably a further dimension). Here I reflect on how ten years of progress in technology has required changes and the challenge of how any necessary changes might be kept “under the hood” of this blog.

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Examples please of FAIR (data); good and bad.

May 6th, 2018

The site fairsharing.org is a repository of information about FAIR (Findable, Accessible, Interoperable and Reusable) objects such as research data.

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Aromaticity-induced basicity.

April 18th, 2018

The molecules below were discussed in the previous post as examples of highly polar but formally neutral molecules, a property induced by aromatisation of up to three rings. Since e.g. compound 3 is known only in its protonated phenolic form, here I take a look at the basicity of the oxygen in these systems to see if deprotonation of the ionic phenol form to the neutral polar form is viable.

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A record polarity for a neutral compound?

April 13th, 2018

In several posts a year or so ago I considered various suggestions for the most polar neutral molecules, as measured by the dipole moment. A record had been claimed[cite]10.1002/anie.201508249[/cite] for a synthesized molecule of ~14.1±0.7D. I pushed this to a calculated 21.7D for an admittedly hypothetical and unsynthesized molecule. Here I propose a new family of compounds which have the potential to extend the dipole moment for a formally neutral molecule up still further.

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The dark satanic mills (of the industrial revolution?)

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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