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	hartrees
Energy at 0K	-153.485577
Energy at 298.15K	-153.485053
HF Energy	-153.485577
Nuclear repulsion energy	77.011227

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3489	3352	0.00
2	Σ_g	2301	2210	0.00
3	Σ_g	925	889	0.00
4	Σ_u	3491	3354	181.13
5	Σ_u	2127	2044	0.64
6	Π_g	740	711	0.00
6	Π_g	740	711	0.00
7	Π_g	620	595	0.00
7	Π_g	620	595	0.00
8	Π_u	618	593	95.35
8	Π_u	618	593	95.35
9	Π_u	273	262	5.14
9	Π_u	273	262	5.14

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.684
C2	0.000	0.000	-0.684
C3	0.000	0.000	1.897
C4	0.000	0.000	-1.897
H5	0.000	0.000	2.962
H6	0.000	0.000	-2.962

	C1	C2	C3	C4	H5	H6
C1		1.3687	1.2125	2.5811	2.2779	3.6466
C2	1.3687		2.5811	1.2125	3.6466	2.2779
C3	1.2125	2.5811		3.7936	1.0654	4.8590
C4	2.5811	1.2125	3.7936		4.8590	1.0654
H5	2.2779	3.6466	1.0654	4.8590		5.9245
H6	3.6466	2.2779	4.8590	1.0654	5.9245

atom1	atom2	atom3	angle		atom1	atom2	atom3	angle
C1	C2	C4	180.000		C1	C3	H5	180.000
C2	C1	C3	180.000		C2	C4	H6	180.000

All results from a given calculation for C₄H₂ (Diacetylene)

using model chemistry: B3LYP/6-31G**

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	0.668
2	C	0.668
3	C	-0.868
4	C	-0.868
5	H	0.200
6	H	0.200

<r²>	78.598
(<r²>)^1/2	8.866

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B3LYP/6-31G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)