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	hartrees
Energy at 0K	-154.298738
Energy at 298.15K
HF Energy	-153.688252
Nuclear repulsion energy	98.390000

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A_g	3273	3152
2	A_g	1548	1490
3	A_g	1116	1075
4	A_g	954	919
5	A_u	577	556
6	A_u	550i	530i
7	B_1g	716	689
8	B_1u	3262	3141
9	B_1u	1563	1505
10	B_1u	1053	1014
11	B_2g	370	357
12	B_2u	3242	3122
13	B_2u	1268	1221
14	B_2u	714	687
15	B_3g	3228	3109
16	B_3g	1188	1144
17	B_3g	859	827
18	B_3u	539	519

Atom	y (Å)	z (Å)
C1	0.674	0.788
C2	0.674	-0.788
C3	-0.674	0.788
C4	-0.674	-0.788
H5	1.442	1.548
H6	1.442	-1.548
H7	-1.442	1.548
H8	-1.442	-1.548

	C1	C2	C3	C4	H5	H6	H7	H8
C1		1.5753	1.3474	2.0729	1.0814	2.4592	2.2485	3.1518
C2	1.5753		2.0729	1.3474	2.4592	1.0814	3.1518	2.2485
C3	1.3474	2.0729		1.5753	2.2485	3.1518	1.0814	2.4592
C4	2.0729	1.3474	1.5753		3.1518	2.2485	2.4592	1.0814
H5	1.0814	2.4592	2.2485	3.1518		3.0968	2.8844	4.2320
H6	2.4592	1.0814	3.1518	2.2485	3.0968		4.2320	2.8844
H7	2.2485	3.1518	1.0814	2.4592	2.8844	4.2320		3.0968
H8	3.1518	2.2485	2.4592	1.0814	4.2320	2.8844	3.0968

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	90.000	C1	C2	H6	134.710
C1	C3	C4	90.000	C1	C3	H7	135.290
C2	C1	C3	90.000	C2	C1	H5	134.710
C2	C4	C3	90.000	C3	C1	H5	135.290
C4	C2	H6	135.290	C4	C3	H7	134.710

All results from a given calculation for C₄H₄ (cyclobutadiene)

using model chemistry: MP4/TZVP

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/TZVP

States and conformations

All results from a given calculation for C₄H₄ (cyclobutadiene)