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 C₄H₉

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C(CH3)3	1605738	Tert-butyl radical	0.0
b	CH3CHCH2CH3	2348552	2-Butyl radical	15.9
c	CH2CH(CH3)2	4630459	Isobutyl radical	21.2