Conferences can be intense, and this one is no exception. After five days, saturation is in danger of setting in. But before it does, I include two more (very) brief things I have learnt.
August 31, 2017
One more WATOC 2017 Report.
Filed under: Interesting chemistry,WATOC reports — Tags: gas phase, journalist, Magnetism, Pavel Hobza, Saturation, Semiconductors - NEC, synthetic chemist, ultrasound — Henry Rzepa @ 12:19 pm
August 29, 2017
(another) WATOC 2017 report.
Filed under: Interesting chemistry,WATOC reports — Tags: chemical shifts, Chemistry, City: Munich, Jan Jenson, metal fall, Munich, Odile Eisenstein, Quotation, speaker, Stefan Grimme, Transition metal, Walter Thiel, World Association of Theoretical and cOmputational Chemists — Henry Rzepa @ 1:45 pm
Another selection (based on my interests, I have to repeat) from WATOC 2017 in Munich.
- Odile Eisenstein gave a talk about predicted 13C chemical shifts in transition metal (and often transient) complexes, with the focus on metallacyclobutanes. These calculations include full spin-orbit/relativistic corrections, essential when the carbon is attached to an even slightly relativistic element. She noted that the 13C shifts of the carbons attached to the metal fall into two camps, those with δ ~+80 ppm and those with values around -8 ppm. These clusters are associated with quite different reactivities, and also seem to cluster according to the planarity or non-planarity of the 4-membered ring. There followed some very nice orbital explanations which I cannot reproduce here because my note taking was incomplete, including discussion of the anisotropy of the solid state spectra. A fascinating story, which I add to here in a minor aspect. Here is a plot of the geometries of the 52 metallacyclobutanes found in the Cambridge structure database. The 4-ring can be twisted by up to 60° around either of the C-C bonds in the ring, and rather less about the M-C bonds. There is a clear cluster (red spot) for entirely flat rings, and perhaps another at around 20° for bent ones, but of interest is that it does form something of a continuum. What is needed is to correlate these geometries with the observed 13C chemical shifts to see if the two sets of clusters match. I include this here because in part such a search can be done in “real-time” whilst the speaker is presenting, and can then be offered as part of the discussion afterwards. It did not happen here because I was chairing the meeting, and hence concentrating entirely on proceedings!
WATOC 2017 report.
Filed under: Interesting chemistry,WATOC reports — 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 — Henry Rzepa @ 7:00 am
October 9, 2014
WATOC2014 Conference report. Emergent themes.
Filed under: Interesting chemistry,WATOC reports — Tags: Complex Biological Systems, condensation, gas-phase molecular species, metal surface catalysis, molecular systems, non-crystalline systems, organic chemist, organometallic systems, potential energy surface, representative, Stefan Grimme, Thus Emily Carter — Henry Rzepa @ 11:21 am
This second report highlights two “themes”, or common ideas that seem to emerge spontaneously from diversely different talks. Most conferences do have them.