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	hartrees
Energy at 0K	-154.368445
Energy at 298.15K
HF Energy	-153.675150
Nuclear repulsion energy	98.099800

Atom	y (Å)	z (Å)
C1	0.676	0.789
C2	0.676	-0.789
C3	-0.676	0.789
C4	-0.676	-0.789
H5	1.447	1.553
H6	1.447	-1.553
H7	-1.447	1.553
H8	-1.447	-1.553

	C1	C2	C3	C4	H5	H6	H7	H8
C1		1.5786	1.3523	2.0786	1.0850	2.4658	2.2561	3.1612
C2	1.5786		2.0786	1.3523	2.4658	1.0850	3.1612	2.2561
C3	1.3523	2.0786		1.5786	2.2561	3.1612	1.0850	2.4658
C4	2.0786	1.3523	1.5786		3.1612	2.2561	2.4658	1.0850
H5	1.0850	2.4658	2.2561	3.1612		3.1061	2.8936	4.2450
H6	2.4658	1.0850	3.1612	2.2561	3.1061		4.2450	2.8936
H7	2.2561	3.1612	1.0850	2.4658	2.8936	4.2450		3.1061
H8	3.1612	2.2561	2.4658	1.0850	4.2450	2.8936	3.1061

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	90.000	C1	C2	H6	134.743
C1	C3	C4	90.000	C1	C3	H7	135.257
C2	C1	C3	90.000	C2	C1	H5	134.743
C2	C4	C3	90.000	C3	C1	H5	135.257
C4	C2	H6	135.257	C4	C3	H7	134.743

All results from a given calculation for C₄H₄ (cyclobutadiene)

using model chemistry: MP4=FULL/6-311G**

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for C4H4 (cyclobutadiene)

using model chemistry: MP4=FULL/6-311G**

States and conformations

All results from a given calculation for C₄H₄ (cyclobutadiene)