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: MP2=FULL/cc-pVDZ

formula	sketch		Energy (kJ mol-1)		Name		difference
	A	B	calculated	experiment	A	B
C3H4			-18	-7	allene	propyne	-12
C4H6			-31	-17	1,2-Butadiene	2-Butyne	-14
C4H6			-64	-82	1-Methylcyclopropene	1,2-Butadiene	18
C4H6			40	42	Methylenecyclopropane	1-Methylcyclopropene	-2
C4H6			-52	-51	1,2-Butadiene	1,3-Butadiene	-1
C4H6			-40	-49	Cyclobutene	1,3-Butadiene	9
C4H6			-9	3	1,2-Butadiene	1-Butyne	-12
C3H6O			-127	-110	Oxetane	Propanal	-17
C4H8			-18	-33	cyclobutane	1-Butene	15