Carbon dichalcogenides are chemical compounds of carbon and chalcogen elements. They have the general chemical formula CZ2, where Z = O, S, Se, Te. This includes:
Carbon dioxide, CO2 Carbon disulfide, CS2 Carbon diselenide, CSe2 Carbonyl sulfide, OCS Carbonyl selenide, OCSe Thiocarbonyl selenide, SCSe Thiocarbonyl telluride, SCTe
Stability 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. This trend is an example of the double bond rule.
Bonding 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.
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