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	hartrees
Energy at 0K	-153.473433
Energy at 298.15K	-153.472698
HF Energy	-153.473433
Nuclear repulsion energy	77.468220

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3474	3324	0.00
2	Σ_g	2333	2231	0.00
3	Σ_g	911	871	0.00
4	Σ_u	3474	3324	178.74
5	Σ_u	2146	2053	3.92
6	Π_g	670	641	0.00
6	Π_g	670	641	0.00
7	Π_g	530	507	0.00
7	Π_g	530	507	0.00
8	Π_u	678	649	82.79
8	Π_u	678	649	82.79
9	Π_u	228	218	11.29
9	Π_u	228	218	11.29

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.686
C2	0.000	0.000	-0.686
C3	0.000	0.000	1.885
C4	0.000	0.000	-1.885
H5	0.000	0.000	2.948
H6	0.000	0.000	-2.948

	C1	C2	C3	C4	H5	H6
C1		1.3710	1.1996	2.5706	2.2622	3.6332
C2	1.3710		2.5706	1.1996	3.6332	2.2622
C3	1.1996	2.5706		3.7702	1.0625	4.8328
C4	2.5706	1.1996	3.7702		4.8328	1.0625
H5	2.2622	3.6332	1.0625	4.8328		5.8953
H6	3.6332	2.2622	4.8328	1.0625	5.8953

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: wB97X-D/aug-cc-pVTZ

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	0.943
2	C	0.943
3	C	-1.061
4	C	-1.061
5	H	0.118
6	H	0.118

<r²>	78.317
(<r²>)^1/2	8.850

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: wB97X-D/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)