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	hartrees
Energy at 0K	-153.424242
Energy at 298.15K	-153.423947
HF Energy	-153.424242
Nuclear repulsion energy	76.929045

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3481	3315	0.00
2	Σ_g	2352	2240	0.00
3	Σ_g	925	880	0.00
4	Σ_u	3482	3315	207.03
5	Σ_u	2160	2057	1.93
6	Π_g	839	798	0.00
6	Π_g	839	798	0.00
7	Π_g	660	628	0.00
7	Π_g	660	628	0.00
8	Π_u	731	696	120.11
8	Π_u	731	696	120.11
9	Π_u	273	260	11.96
9	Π_u	273	260	11.96

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.690
C2	0.000	0.000	-0.690
C3	0.000	0.000	1.899
C4	0.000	0.000	-1.899
H5	0.000	0.000	2.966
H6	0.000	0.000	-2.966

	C1	C2	C3	C4	H5	H6
C1		1.3807	1.2085	2.5892	2.2757	3.6564
C2	1.3807		2.5892	1.2085	3.6564	2.2757
C3	1.2085	2.5892		3.7976	1.0672	4.8649
C4	2.5892	1.2085	3.7976		4.8649	1.0672
H5	2.2757	3.6564	1.0672	4.8649		5.9321
H6	3.6564	2.2757	4.8649	1.0672	5.9321

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: M06-2X/6-31+G**

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	0.467
2	C	0.467
3	C	-0.746
4	C	-0.746
5	H	0.280
6	H	0.280

<r²>	79.299
(<r²>)^1/2	8.905

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: M06-2X/6-31+G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)