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 C₅H₁₀

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH2CHCH2CH2CH3	109671	1-pentene
b	C5H10	287923	Cyclopentane	0.0
c	C5H10	513359	2-Butene, 2-methyl-	31.1
d	C5H10	563462	1-Butene, 2-methyl-	36.3
e	C5H10	627203	2-Pentene, (Z)-	45.8
f	C5H10	646048	2-Pentene, (E)-	39.9
g	C5H10	1630940	Cyclopropane, 1,1-dimethyl-	65.3