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 C₃H₄

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH3CCH	74997	propyne	0.0
b	CH2CCH2	463490	allene	6.8
c	C3H4	2781853	cyclopropene	94.2