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 C₆H₈

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C6H8	592574	1,3-Cyclohexadiene	0.0
b	C6H8	628411	1,4-Cyclohexadiene	2.8
c	C6H8	930267	3-Methylenecyclopentene	9.3
d	C6H8	694019	Bicyclo[3.1.0]hex-2-ene	52.0
e	C6H8	821078	(E)-hexa-1,3,5-triene	61.6
f	C6H8	2612466	(Z)-hexa-1,3,5-triene	65.8
g	C6H8	822413	Bicyclo[2.1.1]hex-2-ene	144.8
h	C6H8	59660649	(Z)-hexa-2,3,4-triene	158.6
i	C6H8	59660650	(E)-hexa-2,3,4-triene	158.6
j	C6H8	30830207	Bicyclo[2.2.0]hex-1(4)-ene	197.6