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 C₄H₅N

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH2CHCH2CN	109751	Allylcyanide
b	C4H5N	109977	Pyrrole	0.0
c	C4H5N	627269	(E)-2-Butenenitrile	28.3
d	C4H5N	1190767	(Z)-2-Butenenitrile	21.8
e	C4H5N	5500210	Cyclopropanecarbonitrile
f	C4H5N	9000366	3H-pyrrole
g	C4H5N	9000377	2H-pyrrole