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	hartrees
Energy at 0K	-153.455828
Energy at 298.15K
HF Energy	-153.455828
Nuclear repulsion energy	77.331603

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3482	3331	0.00
2	Σ_g	2337	2235	0.00
3	Σ_g	912	873	0.00
4	Σ_u	3483	3331	174.83
5	Σ_u	2144	2051	0.98
6	Π_g	692	662	0.00
6	Π_g	692	662	0.00
7	Π_g	534	510	0.00
7	Π_g	534	510	0.00
8	Π_u	693	663	82.09
8	Π_u	693	663	82.09
9	Π_u	229	219	9.49
9	Π_u	229	219	9.49

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	1.889
C4	0.000	0.000	-1.889
H5	0.000	0.000	2.953
H6	0.000	0.000	-2.953

	C1	C2	C3	C4	H5	H6
C1		1.3729	1.2025	2.5754	2.2663	3.6392
C2	1.3729		2.5754	1.2025	3.6392	2.2663
C3	1.2025	2.5754		3.7778	1.0638	4.8416
C4	2.5754	1.2025	3.7778		4.8416	1.0638
H5	2.2663	3.6392	1.0638	4.8416		5.9054
H6	3.6392	2.2663	4.8416	1.0638	5.9054

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/6-311G**

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	-0.068
2	C	-0.068
3	C	-0.059
4	C	-0.059
5	H	0.127
6	H	0.127

<r²>	78.402
(<r²>)^1/2	8.854

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: wB97X-D/6-311G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)