Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Relative enthalpies of isomers - Comparison of 0K enthalpies (kJ mol^-1)

Isomers of C₂H₂N₂

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	HNCCNH	20815456	Ethenediimine
b	H2CNCN	43730263	cyanamide, methylene