Carbon dichalcogenides are chemical compounds of carbon and chalcogen elements. They have the general chemical formula CZ2, where Z = O, S, Se, Te.[1][2]

This includes:

  • Carbon dioxide, CO2
  • Carbon disulfide, CS2
  • Carbon diselenide, CSe2
  • Carbonyl sulfide, OCS
  • Carbonyl selenide, OCSe
  • Thiocarbonyl selenide, SCSe
  • Thiocarbonyl telluride, SCTe[1]

Stability

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Double bonds between carbon and chalcogen elements, C=Z, become weaker the heavier the chalcogen, Z. This trend means carbon dichalcogenide monomers are less stable and more susceptible to polymerisation as Z changes from O to Te. For example, CO2 is stable, CS2 polymerises under extreme conditions, CSe2 tends to polymerise, CSeTe is unstable and CTe2 does not exist.[1] This trend is an example of the double bond rule.

Bonding

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In carbon dichalcogenides, C=O bond lengths are around 1.16 Å, C=S around 1.56 Å, C=Se around 1.70 Å and C=Te around 1.90 Å.[3]

Carbon–chalcogen double bond lengths in carbon dichalcogenides, Z=C=Z′
Species Formula Z Z′ Bond Bond in molecule Bond length / Å Method of determination Reference
Carbon dioxide CO2 O O C=O O=C=O 1.163 infrared spectroscopy [1][3][4]
Carbonyl sulfide OCS O S C=O S=C=O 1.158 microwave spectroscopy [5]
Carbonyl selenide OCSe O Se C=O Se=C=O 1.159 microwave spectroscopy [3]
Carbonyl sulfide OCS O S C=S O=C=S 1.560 microwave spectroscopy [5]
Carbon disulfide CS2 S S C=S S=C=S 1.553 infrared spectroscopy [5]
Thiocarbonyl selenide SCSe S Se C=S Se=C=S 1.553 microwave spectroscopy [5]
Thiocarbonyl telluride SCTe S Te C=S Te=C=S 1.557 microwave spectroscopy [3][5][6]
Carbonyl selenide OCSe O Se C=Se O=C=Se 1.709 microwave spectroscopy [5]
Thiocarbonyl selenide SCSe S Se C=Se S=C=Se 1.693 microwave spectroscopy [5]
Carbon diselenide CSe2 Se Se C=Se Se=C=Se 1.689 neutron diffraction [7]
Thiocarbonyl telluride SCTe S Te C=Te S=C=Te 1.904 microwave spectroscopy [3][5][6]

References

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  1. ^ a b c d Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. pp. 306, 314–319, 754–755. ISBN 978-0-08-037941-8.
  2. ^ Housecroft, C. E.; Sharpe, A. G. (2008). Inorganic Chemistry (3rd ed.). Prentice Hall. pp. 409–412, 423–425. ISBN 978-0-13-175553-6.
  3. ^ a b c d e Wells, A. F. (1984). Structural Inorganic Chemistry (5th ed.). Oxford University Press. p. 926. ISBN 978-0-19-965763-6.
  4. ^ Plyler, Earle K.; Blaine, Lamdin R.; Tidwell, Eugene D. (1955). "Infrared absorption and emission spectra of carbon monoxide in the region from 4 to 6 microns". Journal of Research of the National Bureau of Standards. 55 (4): 183–192. doi:10.6028/jres.055.019.
  5. ^ a b c d e f g h William M. Haynes, ed. (2012). CRC Handbook of Chemistry and Physics (93rd ed.). CRC Press. p. 9–33. ISBN 978-1439880500.
  6. ^ a b Hardy, W. A.; Silvey, G. (1954). "Microwave Spectrum of TeCS and Masses of the Stable Tellurium Isotopes". Phys. Rev. 95 (2): 385–. doi:10.1103/PhysRev.95.385.
  7. ^ Powell, B. M.; Torrie, B. H. (1983). "Structure of solid carbon diselenide (CSe2) at 17.5, 50 and 200K". Acta Crystallogr. C. 39 (8): 3070–3072. doi:10.1107/S0108270183007015.