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	hartrees
Energy at 0K	-154.290154
Energy at 298.15K	-154.293024
HF Energy	-153.674878
Nuclear repulsion energy	98.006810

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A_g	3253	3155
2	A_g	1539	1493
3	A_g	1113	1079
4	A_g	953	924
5	A_u	734	711
6	A_u	469	455
7	B_1g	798	773
8	B_1u	3242	3144
9	B_1u	1555	1508
10	B_1u	1041	1010
11	B_2g	520	504
12	B_2u	3221	3123
13	B_2u	1255	1217
14	B_2u	721	699
15	B_3g	3207	3110
16	B_3g	1168	1133
17	B_3g	855	829
18	B_3u	558	541

Atom	y (Å)	z (Å)
C1	0.677	0.790
C2	0.677	-0.790
C3	-0.677	0.790
C4	-0.677	-0.790
H5	1.448	1.555
H6	1.448	-1.555
H7	-1.448	1.555
H8	-1.448	-1.555

	C1	C2	C3	C4	H5	H6	H7	H8
C1		1.5807	1.3534	2.0809	1.0855	2.4683	2.2575	3.1640
C2	1.5807		2.0809	1.3534	2.4683	1.0855	3.1640	2.2575
C3	1.3534	2.0809		1.5807	2.2575	3.1640	1.0855	2.4683
C4	2.0809	1.3534	1.5807		3.1640	2.2575	2.4683	1.0855
H5	1.0855	2.4683	2.2575	3.1640		3.1091	2.8951	4.2483
H6	2.4683	1.0855	3.1640	2.2575	3.1091		4.2483	2.8951
H7	2.2575	3.1640	1.0855	2.4683	2.8951	4.2483		3.1091
H8	3.1640	2.2575	2.4683	1.0855	4.2483	2.8951	3.1091

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	90.000	C1	C2	H6	134.751
C1	C3	C4	90.000	C1	C3	H7	135.249
C2	C1	C3	90.000	C2	C1	H5	134.751
C2	C4	C3	90.000	C3	C1	H5	135.249
C4	C2	H6	135.249	C4	C3	H7	134.751

All results from a given calculation for C₄H₄ (cyclobutadiene)

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

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: MP4/6-311G**

States and conformations

All results from a given calculation for C₄H₄ (cyclobutadiene)