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: MP3/6-31+G**

formula	sketch		Energy (kJ mol-1)		Name		difference
	A	B	calculated	experiment	A	B
C3H4			-2	-7	allene	propyne	4
C3H6O			-107	-110	Oxetane	Propanal	3
C4H8			-41	-33	cyclobutane	1-Butene	-9