Bonjour
En chimie "standard", on nous apprend que seuls les électrons de la dernière couche sont impliqués dans les réactions chimiques. Connait-on des exceptions à cette règle? Quelles en seraient les conséquences?
Je pose la question après avoir vu une discussion sur le sujet du "mercure rouge"; celui-ci semble être de la joyeuse faribole, par contre je me demande si cet aspect est vraisemblable.
Pour référence, voici un extrait de la discussion:
MerciBarnaby's group has talked to four unnamed scientists in Russia. Barnaby says all
four provided detailed information about red mercury. As a result Barnaby has
concluded that it is a polymer with a gel-like consistency in which mercury and antimony
have been bound together after irradiation for up to 20 days in a nuclear reactor.
He says that mercury antimony oxide is produced in "relatively large quantities" at a
chemicals factory in Yekaterinburg. Red mercury itself, he claims, was first produced in
1965 in a cyclotron at the nuclear research centre at Dubna, near Moscow, and is now
made at "a number" of Russian military centres, including Krasnoyarsk in Siberia and
Penza, 500 kilometres souh_ east of Moscow. One Russian scientist estimates that
Russia produces about 60 kilograms of red mercury a year.
Barnaby argues that the gel, as well as having possible uses in fission weapons,
could yield enough chemical energy when compressed to fuse tritium atoms and
produce a thermonuclear explosion. The gel may already be incorporated in Russian
neutron weapons, such as the M-1975 240-millimetre mortar, he says.
If this is true, red mercury would be a remarkable material which could have dramatic
implications for energy production as well as weapons technology. But its existence is
doubted, not just by the British, US and German governments (This Week, 6 June
1992), but also by independent critics. Two of the most notable are Joseph Rotblat,
emeritus professor of physics at the University of London, and Ted Taylor, a leading
bomb designer at the US nuclear weapons laboratory at Los Alamos in New Mexico in
the 1950s.
Taylor points out that the only conceivable way to obtain the high levels of chemical
energy claimed for red mercury would be to dislodge the inner electrons of mercury and
antimony. But he argues that it is difficult to see how this could produce a substance
that was stable long enough to be used as an explosive. "I would bet that it does not
exist," he says.
Despite his scepticism, Taylor believes that the potential implications of red mercury
are so significant that it ought to be investigated. The discovery of material that could
release hundreds or thousands of times more chemical energy than TNT could be
"more important than nuclear fission", he says. it could revolutionise space travel as
well as making possible a fearsome new category of nuclear fusion weapons. "I hope
it's all wrong, but maybe I'm slipping into wishful thinking," he says. He agrees with
Barnaby and Cohen that trade in tritium ought to be subject to the same safeguards as
plutonium and highly enriched uranium, the essential ingredients of fission bombs.
Cohen, however, claims that red mercury is one of a new class of highly explosive
materials under secret investigation by nuclear weapons scientists in the US. He quotes
a memorandum which he received recently from Sandia National Laboratories, the
nuclear weapons engineering centre in New Mexico, which describes such materials as
"ballotechnic". According to the memo, this means that "under certain conditions" the
chemical energy obtained "can be greater than with high explosives".
Bob Graham, a senior researcher at Sandia, says that he coined the term
"ballotechnics" to describe devices which produce heat following exposure to shock.
But he insists that it has no connection with red mercury, which he does not believe
exists. "Graham is not free to speak openly about this," counters Cohen. "I am."
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