Editing Cyanogen (section)

==Paracyanogen==
[[File:Paracyanogen.png|thumb|left|class=skin-invert-image]] Paracyanogen is a [[polymer]] of cyanogen. It can be best prepared by heating [[mercury(II) cyanide]]. It can also be prepared by heating [[silver cyanide]], [[silver cyanate]], [[cyanogen iodide]] or cyanuric iodide.<ref>{{cite journal |last= Bircumshaw |first= L. L. |author2=F. M. Tayler |author3=D. H. Whiffen |year=1954 |title= Paracyanogen: its formation and properties. Part I| journal= J. Chem. Soc. |pages=931–935 |doi=10.1039/JR9540000931}}</ref> It can also be prepared by the polymerization of cyanogen at {{convert|300|to|500|C}} in the presence of trace impurities. Paracyanogen can also be converted back to cyanogen by heating to {{convert|800|C}}.<ref name=greenwood/> Based on experimental evidence, the structure of this polymeric material is thought to be rather irregular, with most of the [[carbon]] atoms being of [[Orbital hybridization#sp2|sp{{sup|2}} type]] and localized domains of [[Conjugated system|π conjugation]].<ref>{{cite journal|author=Maya, Leon|year=1993|journal=Journal of Polymer Science Part A|volume= 31|issue=10|pages= 2595–2600|title=Paracyanogen Reexamined |doi=10.1002/pola.1993.080311020 |bibcode=1993JPoSA..31.2595M |url=https://zenodo.org/record/1229357 |type=Submitted manuscript}}</ref>