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 C₆H₄

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C6H4	462806	Benzyne	0.0
b	C6H4	16668681	(E)-Hexa-1,5-diyne-3-ene	98.1
c	C6H4	16668670	(Z)-Hexa-1,5-diyne-3-ene	101.8