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	hartrees
Energy at 0K	-154.614963
Energy at 298.15K	-154.618058
HF Energy	-154.614963
Nuclear repulsion energy	98.933654

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3279	3152	0.00
2	A_g	1670	1606	0.00
3	A_g	1125	1082	0.00
4	A_g	964	927	0.00
5	A_u	894	859	0.00
6	A_u	535	514	0.00
7	B_1g	887	853	0.00
8	B_1u	3267	3140	19.91
9	B_1u	1676	1611	2.82
10	B_1u	1046	1005	0.33
11	B_2g	613	589	0.00
12	B_2u	3244	3118	9.53
13	B_2u	1258	1209	37.68
14	B_2u	740	711	9.31
15	B_3g	3226	3101	0.00
16	B_3g	1173	1128	0.00
17	B_3g	836	803	0.00
18	B_3u	598	575	109.73

Atom	y (Å)	z (Å)
C1	0.667	0.783
C2	0.667	-0.783
C3	-0.667	0.783
C4	-0.667	-0.783
H5	1.437	1.551
H6	1.437	-1.551
H7	-1.437	1.551
H8	-1.437	-1.551

	C1	C2	C3	C4	H5	H6	H7	H8
C1		1.5667	1.3332	2.0571	1.0878	2.4584	2.2395	3.1425
C2	1.5667		2.0571	1.3332	2.4584	1.0878	3.1425	2.2395
C3	1.3332	2.0571		1.5667	2.2395	3.1425	1.0878	2.4584
C4	2.0571	1.3332	1.5667		3.1425	2.2395	2.4584	1.0878
H5	1.0878	2.4584	2.2395	3.1425		3.1023	2.8743	4.2292
H6	2.4584	1.0878	3.1425	2.2395	3.1023		4.2292	2.8743
H7	2.2395	3.1425	1.0878	2.4584	2.8743	4.2292		3.1023
H8	3.1425	2.2395	2.4584	1.0878	4.2292	2.8743	3.1023

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	90.000	C1	C2	H6	134.897
C1	C3	C4	90.000	C1	C3	H7	135.103
C2	C1	C3	90.000	C2	C1	H5	134.897
C2	C4	C3	90.000	C3	C1	H5	135.103
C4	C2	H6	135.103	C4	C3	H7	134.897

All results from a given calculation for C₄H₄ (cyclobutadiene)

using model chemistry: B1B95/cc-pVDZ

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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Number	Element	Mulliken
1	C	0.008
2	C	0.008
3	C	0.008
4	C	0.008
5	H	-0.008
6	H	-0.008
7	H	-0.008
8	H	-0.008

<r²>	57.609
(<r²>)^1/2	7.590

All results from a given calculation for C4H4 (cyclobutadiene)

using model chemistry: B1B95/cc-pVDZ

States and conformations

All results from a given calculation for C₄H₄ (cyclobutadiene)