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 C₉H₈

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	C9H8	95136	Indene
b	C9H8	14867835	spiro[4.4]nona-1,3,6,8-tetraene