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 C₅H₆

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C5H6	35634107	Propellane
b	C5H6	542927	1,3-Cyclopentadiene	0.0
c	C5H6	1574409	3-Penten-1-yne, (Z)-	123.9
d	C5H6	78808	1-Buten-3-yne, 2-methyl-	124.3
e	C5H6	2004695	3-Penten-1-yne, (E)-	124.7
f	C5H6	6746947	Cyclopropylacetylene	157.7
g	C5H6	5164352	Bicyclo[2.1.0]pent-2-ene	198.7