Posts Tagged ‘Physics’
Friday, 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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Tags:aromatisation stabilization energy, Chemical polarity, chemical properties, Chemistry, Dipole, Electric dipole moment, Electromagnetism, energy, Moment, Nature, Physical quantities, Physics, Potential theory
Posted in Interesting chemistry | 11 Comments »
Tuesday, August 29th, 2017
The triennial conference is this year located in Munich. With 1500 participants and six parallel sessions, this report can give only a flavour of proceedings.
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Tags:bond dissociation energy, City: Aachen, City: Munich, Dieter Cremer, Edward Valeev, energy, Flavour, Jeremy Harvey, Ken Houk, Leo Radom, Peter Scheiner, Physics, Proceedings, Quark matter, Standard Model, Yitzhak Apeloig
Posted in Interesting chemistry, WATOC reports | No Comments »
Friday, June 2nd, 2017
In 2016, the world heard that gravitational waves had been detected and now a third instance is reported.‡ Given that the data associated with these detections are perhaps amongst the most important instances in recent times, I thought I might take a peek at how it was managed.
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Tags:Astronomy, Binary stars, Black holes, famous chemical controversy, General relativity, Gravitational wave, Gravity, Physics, search procedures, Technology/Internet, Wave
Posted in Chemical IT | 1 Comment »
Sunday, March 5th, 2017
Cyclobutadiene is one of those small iconic molecules, the transience and instability of which was explained theoretically long before it was actually detected in 1965.[cite]10.1021/ja01092a049[/cite] Given that instability, I was intrigued as to how many crystal structures might have been reported for this ring system, along with the rather more stable congener cyclo-octatetraene. Here is what I found.
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Tags:antiaromaticity, Chemistry, cyclobutadiene, Instability, Nature, Physical organic chemistry, Physics, search query
Posted in crystal_structure_mining | 4 Comments »
Wednesday, February 15th, 2017
This post arose from a comment attached to the post on Na2He and relating to peculiar and rare topological features of the electron density in molecules called non-nuclear attractors. This set me thinking about other molecules that might exhibit this and one of these is shown below.
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Tags:Attractor, brief search, Chemistry, Electron, Electron density, Hydrogen, Molecule, Nature, Physics, Quantum chemistry
Posted in Interesting chemistry | 11 Comments »
Saturday, February 11th, 2017
On February 6th I was alerted to this intriguing article[cite]10.1038/nchem.2716[/cite] by a phone call, made 55 minutes before the article embargo was due to be released. Gizmodo wanted to know if I could provide an (almost)† instant‡ quote. After a few days, this report of a stable compound of helium and sodium still seems impressive to me and I now impart a few more thoughts here.
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Tags:10.1038, Atom, Chemical elements, chemical phenomenon, Chemistry, Company: P. Acucar-CBD, Electride, Electron, Food Retail & Distribution - NEC, helium, Hydrogen, Matter, Oxygen, Physics, social media
Posted in Bond slam, crystal_structure_mining, Interesting chemistry | 11 Comments »
Saturday, December 24th, 2016
The previous posts produced discussion about the dipole moments of highly polar molecules. Here to produce some reference points for further discussion I look at the dipole moment of glycine, the classic zwitterion (an internal ion-pair).
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Tags:aqueous solution, Chemical polarity, Chemistry, dielectric, Dipole, Electric dipole moment, Electromagnetism, Magnetism, Moment, Nature, Physical quantities, Physics, Potential theory, zwitterion
Posted in crystal_structure_mining, Interesting chemistry | 1 Comment »
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. 
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Tags:chemical bonding, chemical reaction, Chemistry, Delocalized electron, double bond, energy, energy difference, HOMO/LUMO, lowest energy, Molecular orbital, Natural bond orbital, Nature, Physics, Quantum chemistry, stable HOMO-1
Posted in reaction mechanism | No Comments »