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 C₃H₄O₂

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C3H4O2	78988	Methyl glyoxal
b	C3H4O2	542789	propanedial
c	C3H4O2	9000128	propenalol
d	HOCHCCHOH	9000400	allenediol
e	C3H4O2	79107	2-Propenoic acid	0.0
f	C3H4O2	57578	β–Propiolactone	26.4