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Nicodem
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I noticed this thread a bit late, but nevertheless, since it is not about organic chemistry (at least by product) and since it is mainly just a some
idle talk, I'm moving it to the Miscellaneous section.
There is no way something that monstrous could exist at normal conditions. Just consider the thermodynamic instability of anything crowded like that.
Besides, the reduction of CX4 with metals or electroreduction is known to give graphite (or the corresponding carbides where applicable).
In protic environment the reduction gives partially reduced products like CH2X2. (for a short review, see: Carbyne and
Carbynoid Structures, 1999, pages 198-199).
The closest reduction that gives tetrahedral carbon-based polymeric materials, is the reduction of CHX3 with some alkali and alkaline earth
metals based reducing reagents to give polycarbynes of the structure [HC]n (the carbon is sp3). If allowed to go wildly
speculative, I would say that this material might be a suitable starting material for growing diamond crystals at not particularly high pressures, if
made soluble or volatile and a suitable oxidation system could be applied. Too bad I can't think of any such.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Nicodem
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Thread Moved
21-11-2015 at 02:16 |
alive&kickin
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Didn't Moissan in the 1800s create very small diamonds by mixing charcoal in melted iron and then cooling in a water bath? The idea was that the
contracting iron upon cooling created tremendous pressure upon the trapped carbon.
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Detonationology
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The contraction generated by the cooling supposedly produced the high pressure required to transform graphite into diamond. Moissan published his work
in a series of articles in the 1890s.[7]
Many other scientists tried to replicate his experiments. Sir William Crookes claimed success in 1909.[8] Otto Ruff claimed in 1917 to have produced
diamonds up to 7 mm in diameter,[9] but later retracted his statement.[10] In 1926, Dr. J Willard Hershey of McPherson College replicated Moissan's
and Ruff's experiments,[11][12] producing a synthetic diamond; that specimen is on display at the McPherson Museum in Kansas.[13] Despite the claims
of Moissan, Ruff, and Hershey, other experimenters were unable to reproduce their synthesis
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“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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crystal grower
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Even natural diamonds are slowly changing back to graphite(extremly slowly ) becouse diamond is only high temperature allotrope of carbon.
-Diamonds are "unstable" at normal temperature and pressure and they also can be produced only in conditions which are natural for diamonds (high
temp. and pressure).
[Edited on 10-1-2016 by crystal grower]
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careysub
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Quote: Originally posted by crystal grower  | Even natural diamonds are slowly changing back to graphite(extremly slowly ) becouse diamond is only high temperature allotrope of carbon.
[Edited on 10-1-2016 by crystal grower] |
They are thermodynamically unstable, in that graphite is a lower energy form - but diamonds are not changing to graphite.
Natural diamonds are over one billion years old (dated in a range of 1.2-2.7 billion years old) and clearly are not converting to graphite, despite
the fact that a lot of them spent a lot of their time deep in the crust where it is hot.
This should be placed in the same category as claims of glass flowing at room temperature, i.e. the atomic arrangement is actually stable - unable to
rearrange itself no matter how thermodynamically favored.
See:
http://www.gia.edu/gems-gemology/WN13-advances-diamond-geolo...
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crystal grower
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| Quote: Originally posted by careysub | | Quote: Originally posted by crystal grower | Even natural diamonds are slowly changing back to graphite(extremly slowly ) becouse diamond is only high temperature allotrope of carbon.
[Edited on 10-1-2016 by crystal grower] |
They are thermodynamically unstable, in that graphite is a lower energy form - but diamonds are not changing to graphite.
Natural diamonds are over one billion years old (dated in a range of 1.2-2.7 billion years old) and clearly are not converting to graphite, despite
the fact that a lot of them spent a lot of their time deep in the crust where it is hot.
This should be placed in the same category as claims of glass flowing at room temperature, i.e. the atomic arrangement is actually stable - unable to
rearrange itself no matter how thermodynamically favored.
See:
http://www.gia.edu/gems-gemology/WN13-advances-diamond-geolo... |
Ive heard some scientist saying that diamonds are changing but in extreme time period (but what u re saying makes sense too)
Main thing I wanted to explain was that diamonds cant be produced in normal conditions according thermodynamical stability of diamond.
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PHILOU Zrealone
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Why start a new tread when one already exists?
Growing synthetic diamonds at home
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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