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 C₄H₆O

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH2CHOCHCH2	109933	Vinyl ether
b	C4H6O	1191953	Cyclobutanone
c	C4H6O	1191997	Furan, 2,3-dihydro-
d	C4H6O	1708298	Furan, 2,5-dihydro-
e	CHOCHCHCH3	4170303	2-Butenal
f	C4H6O	15798648	cis-2-butenal