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 C₅H₅NO

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C5H5NO	9000004	3(2H)-Pyridinone
b	C5H5NO	9000015	3(6H)-Pyridinone
c	C5H5NO	9000026	3(4H)-Pyridinone
d	C5H5NO	9000037	2(5H)-Pyridinone
e	C5H5NO	9000048	2(3H)-Pyridinone
f	C5H5NO	9000059	4(3H)-Pryidinone
g	C5H5NO	9000060	4(1H)-Pryidinone
h	C5H5NO	72762006	2(1H)-Pyridinone
i	C5H5NO	109104	2-Pyridinol
j	C5H5NO	109002	3-Pyridinol	0.0
k	C5H5NO	626642	4-Pyridinol	13.4