What I don't understand is how the reactants (before they have bonded) can have a zero point vibration energy. Is it simply a sum of each reactants respective quantum wave lengths?
Harry On Sat, Jan 31, 2015 at 7:23 AM, Roarty, Francis X <[email protected]> wrote: > [snip] "In this scenario, the lightweight muonium atom would move rapidly > between two heavy bromine atoms, 'like a Ping Pong ball bouncing between two > bowling balls,' Fleming says. The oscillating atom would briefly hold the > two bromine atoms together and reduce the overall energy, and therefore > speed, of the reaction.”[/snip] > > > > I wonder if it can form between 2 molecules / lower their energy such that > their disassociation threshold is lower than the energy given off upon the > nearly instantaneous re-association .. could this be our run away mechanism? > In that it is not van der Walls force it represents another force vector > that can oppose the isotropy based on geometry. Previously I have endorsed > H2 as the molecule being discounted and forming an endless reversible > reaction but your citation would suggest the hydrogen proton as the enabler > discounting the bonds of nearby larger atoms but still a ZPE perspective > which I continue to believe is the ultimate source of this anomaly. > > Fran > > > > From: H Veeder [mailto:[email protected]] > Sent: Friday, January 30, 2015 4:35 PM > To: [email protected] > Subject: EXTERNAL: [Vo]:Re: [Vo]:New type of chemical bond discovered > > > > another link > > > Isotope effect produces new type of chemical bond > > http://www.rsc.org/chemistryworld/2014/10/isotope-effect-produces-new-type-chemical-bond > > > > quote <<In the early 1980s it was proposed that in certain transition states > consisting of a very light atom sandwiched between two heavy ones, the > system would be stabilised not by conventional van der Waal’s forces, but by > vibrational bonding, with the light atom shuttling between its two > neighbours. However, despite several groups searching for such a system none > was demonstrated and the hunt fizzled out. > > Now, Jörn Manz, of the Free University of Berlin and Shanxi University in > China, and colleagues believe they have the theoretical and experimental > evidence to demonstrate a stable vibrational bond.>> > > > > > > On Fri, Jan 30, 2015 at 11:34 AM, H Veeder <[email protected]> wrote: > > New type of chemical bonddiscovered > http://www.sciencealert.com/new-type-of-chemical-bond-discovered > > Move over, covalent and ionic bonds, there’s a new chemical bond in town, > and it loves to shake things up. > > It’s taken decades to nail down, but researchers in Canada have finally > identified a new chemical bond, which they’re calling a ‘vibrational bond’. > > This vibrational bond seems to break the law of chemistry that states if you > increase the temperature, the rate of reaction will speed up. Back in 1989, > a team from the University of British Columbia investigated the reactions of > various elements to muonium (Mu) - a strange, hydrogen isotope made up of an > antimuon and an electron. They tried chlorine and fluorine with muonium, and > as they increased the heat, the reaction time sped up, but when they tried > bromine (br), a brownish-red toxic and corrosive liquid, the reaction time > sped up as the temperature decreased. The researchers, Amy Nordrum writes > for Scientific American, "were flummoxed”. > > Perhaps, thought one of the team, chemist Donald Flemming, when the bromine > and muonium made contact, they formed a transitional structure made up of a > lightweight atom flanked by two heavier atoms. And the structure was joined > not byvan der Waal’s forces - as would usually be expected - but by some > kind of temporary ‘vibrational’ bond that had been proposed several years > earlier. > > Nordrum explains: > > "In this scenario, the lightweight muonium atom would move rapidly between > two heavy bromine atoms, 'like a Ping Pong ball bouncing between two bowling > balls,' Fleming says. The oscillating atom would briefly hold the two > bromine atoms together and reduce the overall energy, and therefore speed, > of the reaction.” > > But back then, the team didn’t have the technology needed to actually see > this reaction take place, because it lasts for just a few milliseconds. But > now they do, and the team took their investigation to the nuclear > accelerator at Rutherford Appleton Laboratory in England. > > With the help of theoretical chemists from the Free University of Berlin and > Saitama University in Japan, Flemming’s team watched as the light muonium > and heavy bromine formed a temporary bond. “The lightest isotopomer, BrMuBr, > with Mu the muonium atom, alone exhibits vibrational bonding in accord with > its possible observation in a recent experiment on the Mu + Br2 reaction,” > the team reports in the journal Angewandte Chemie International Edition. > "Accordingly, BrMuBr is stabilised at the saddle point of the potential > energy surface due to a net decrease in vibrational zero point energy that > overcompensates the increase in potential energy.” > > In other words, the vibration in the bond decreased the total energy of the > BrMuBr structure, which means that even when the temperature was increased, > there was not enough energy to see an increase in the reaction time. > > While the team only witnessed the vibrational bond occurring in a bromine > and muonium reaction, they suspect it can also be found in interactions > between lightweight and heavy atoms, where van der Waal’s forces are assumed > to be at play. > > "The work confirms that vibrational bonds - fleeting though they may be - > should be added to the list of known chemical bonds,” says Nordrum at > Scientific American. > > Sorry, future high school chemistry students, here's another thing you'll > probably have to rote learn. > > Source: Scientific American > > > > ----------- > > > > This link has a diagram of the potential energy curve for a vibrational > bond: > > > > A new type of chemical bond has been confirmed – the vibrational bond > > http://www.zmescience.com/science/chemistry/new-kind-chemical-vibrational-bond-0543543/ > > > > > > Harry > > > >
