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 C₃H₄N₂

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C3H4N2	288131	1H-Pyrazole
b	C3H4N2	288324	1H-Imidazole
c	C3H4N2	9000162	4H-Imidazole
d	C3H4N2	9000173	2H-Imidazole