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 C₅H₈O

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C5H8O	120923	Cyclopentanone	0.0
b	C5H8O	1487156	Furan, 2,3-dihydro-5-methyl-	61.9
c	C5H8O	765435	Methyl cyclopropyl ketone	76.8
d	C5H8O	110872	2H-Pyran, 3,4-dihydro-	79.3