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: PBEPBE/aug-cc-pVTZ

formula	sketch		Energy (kJ mol-1)		Name		difference
	A	B	calculated	experiment	A	B
C3H4			14	-7	allene	propyne	21
C4H6			-39	-51	1,2-Butadiene	1,3-Butadiene	12
C4H6			26	3	1,2-Butadiene	1-Butyne	23
C4H6			-5	-17	1,2-Butadiene	2-Butyne	12
C4H6			-47	-49	Cyclobutene	1,3-Butadiene	2
C4H6			-76	-82	1-Methylcyclopropene	1,2-Butadiene	6
C4H6			47	42	Methylenecyclopropane	1-Methylcyclopropene	6
C3H6O			-106	-110	Oxetane	Propanal	4
C4H8			-23	-33	cyclobutane	1-Butene	9