Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Tautomer energy comparison

using model chemistry: CCSD/aug-cc-pVTZ

formula	sketch		Energy (kJ mol-1)		Name		difference
	A	B	calculated	experiment	A	B
C3H4			-4	-7	allene	propyne	2