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Name of structure

  1. May 13, 2006 #1
    Well, we know how quartz and glass are a network SiO2 molecules

    *But what if we replace the Si atoms with carbon? In other words, what if we have the same network arrangement of CO2 molecules?

    -Is there a name for this network solid?

    Perhaps I am referring to "CO2-V", possibly?
    Last edited: May 13, 2006
  2. jcsd
  3. May 14, 2006 #2


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    I don't think I know what you are asking.
    CO2 is a gas, unless its quite cold.
    Then it's usually called dry ice.
  4. May 14, 2006 #3
    I am not referring to dry ice~

    Dry ice is a molecular solid; I'm referring to a network solid,
    with molecular units CO2, just as quartz/glass is SiO2.

    http://www.btinternet.com/~chemistry.diagrams/SIO2-3UN.GIF (<-click on the link)
    The red spheres represent the oxygen atoms,
    and the cyan spheres represent carbon atoms.

    ~Possibly, I may be referring to CO2-V,
    (see http://www.llnl.gov/str/Yoo.html)
    but I am not sure...
    Last edited by a moderator: Apr 22, 2017
  5. May 14, 2006 #4


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    The network solid you describe does not exist at NTP. The reasons for this are the smaller covalent radius of C (compared to Si, which is large enough to accomodate O-atoms in tetrahedral voids) and the higher polarity of CO2 compared to SiO2.

    At very high pressures though, I believe some kind of CO2 network solid has been made.
  6. May 16, 2006 #5
    CO2 won't form a network solid no. C will in the form of coal or diamond and such but you can't compact a gas to form glass
  7. May 17, 2006 #6
    Not under NTP, as Gokul mentioned. But under large pressures...


    it has been done (according to the linked article).
  8. May 18, 2006 #7
    Electron shells

    The reason that CO2 will not form the network solid as iwould silicon or even sulphur is due to the intermediate electron d shell that is present in these but not in carbon. this shell allows silicon to fulfill more energy states and form a more stable compound. but it does prevent it from forming long chain molecule as carbon will, i.e. dodecane
  9. May 18, 2006 #8
    oh wow that had not been brought to my attention until just now

    that's quite useful info, thank you :smile:
  10. Jun 1, 2006 #9
    so can CO2-V be stabilized at all (at NTP) ?? :bugeye:

    (CO2-V being the "quartzlike" CO2 I mentioned earlier)
    Last edited by a moderator: May 2, 2017
  11. Jun 2, 2006 #10


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    That's probably a question that can only be answered by researchers in the field.

    What is well-known is that it has become almost commonplace to be able to stabilize high temperature phases of diffferent systems at well below their equilibrium phase transition temperatures. There hasn't been as much success with stabilizing high pressure phases. This particular phase, the CO2-V is a high temperature and high pressure phase.

    It will take the discovery of a truly rare and well-hidden reaction pathway that cuts through the giant activation energies needed to reach the phase in question. Does such a pathway exist? No idea.
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