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	hartrees
Energy at 0K	-154.390613
Energy at 298.15K
HF Energy	-153.694323
Nuclear repulsion energy	98.465792

Atom	y (Å)	z (Å)
C1	0.674	0.787
C2	0.674	-0.787
C3	-0.674	0.787
C4	-0.674	-0.787
H5	1.439	1.549
H6	1.439	-1.549
H7	-1.439	1.549
H8	-1.439	-1.549

	C1	C2	C3	C4	H5	H6	H7	H8
C1		1.5730	1.3476	2.0713	1.0799	2.4574	2.2458	3.1490
C2	1.5730		2.0713	1.3476	2.4574	1.0799	3.1490	2.2458
C3	1.3476	2.0713		1.5730	2.2458	3.1490	1.0799	2.4574
C4	2.0713	1.3476	1.5730		3.1490	2.2458	2.4574	1.0799
H5	1.0799	2.4574	2.2458	3.1490		3.0975	2.8774	4.2278
H6	2.4574	1.0799	3.1490	2.2458	3.0975		4.2278	2.8774
H7	2.2458	3.1490	1.0799	2.4574	2.8774	4.2278		3.0975
H8	3.1490	2.2458	2.4574	1.0799	4.2278	2.8774	3.0975

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	90.000	C1	C2	H6	134.901
C1	C3	C4	90.000	C1	C3	H7	135.099
C2	C1	C3	90.000	C2	C1	H5	134.901
C2	C4	C3	90.000	C3	C1	H5	135.099
C4	C2	H6	135.099	C4	C3	H7	134.901

All results from a given calculation for C₄H₄ (cyclobutadiene)

using model chemistry: CCSD(T)/cc-pVTZ

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: CCSD(T)/cc-pVTZ

States and conformations

All results from a given calculation for C₄H₄ (cyclobutadiene)