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 C₃H₈N₂O

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	NH2CONHC2H5	625525	Urea, ethyl-	0.0
b	NH(CH3)CONH(CH3)	96311	Urea, N,N'-dimethyl-	35.9
c	N(CH3)2CONH2	598947	Urea, N,N-dimethyl-	37.5