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 298.15K enthalpies (kJ mol^-1)

Isomers of C₂H₂

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	HCCH-	74862	acetylene anion
b	H2CC-	2143693	vinylidene anion	0.0