Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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 C₄H₆N⁺

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C4H6N+	9000911	pyrrole, protonated
b	C4H6N+	910095204	pyrrole, alpha-protonated