Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) 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 CH₅N₂O

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH5N2O+	9000810	urea, N-protonated
b	H2NCOHNH2+	952102862	urea, protonated