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	hartrees
Energy at 0K	-153.413501
Energy at 298.15K	-153.413009
HF Energy	-153.413501
Nuclear repulsion energy

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3505	3324	0.00
2	Σ_g	2356	2235	0.00
3	Σ_g	920	872	0.00
4	Σ_u	3505	3325	157.81
5	Σ_u	2166	2055	0.44
6	Π_g	764	725	0.00
6	Π_g	764	725	0.00
7	Π_g	625	593	0.00
7	Π_g	625	593	0.00
8	Π_u	651	617	102.58
8	Π_u	651	617	102.58
9	Π_u	267	253	7.63
9	Π_u	267	253	7.63

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.688
C2	0.000	0.000	-0.688
C3	0.000	0.000	1.897
C4	0.000	0.000	-1.897
H5	0.000	0.000	2.964
H6	0.000	0.000	-2.964

	C1	C2	C3	C4	H5	H6
C1		1.3769	1.2084	2.5852	2.2760	3.6529
C2	1.3769		2.5852	1.2084	3.6529	2.2760
C3	1.2084	2.5852		3.7936	1.0677	4.8613
C4	2.5852	1.2084	3.7936		4.8613	1.0677
H5	2.2760	3.6529	1.0677	4.8613		5.9289
H6	3.6529	2.2760	4.8613	1.0677	5.9289

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/6-31G*

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	0.678
2	C	0.678
3	C	-0.960
4	C	-0.960
5	H	0.282
6	H	0.282

<r²>	78.486
(<r²>)^1/2	8.859

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: wB97X-D/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)