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	hartrees
Energy at 0K	-153.435937
Energy at 298.15K	-153.435012
HF Energy	-153.435937
Nuclear repulsion energy	77.090536

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3422	3369	0.00
2	Σ_g	2212	2179	0.00
3	Σ_g	908	894	0.00
4	Σ_u	3425	3372	168.47
5	Σ_u	2050	2019	7.34
6	Π_g	606	597	0.00
6	Π_g	606	597	0.00
7	Π_g	500	492	0.00
7	Π_g	500	492	0.00
8	Π_u	606	597	82.33
8	Π_u	606	597	82.33
9	Π_u	228	224	7.95
9	Π_u	228	224	7.95

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.680
C2	0.000	0.000	-0.680
C3	0.000	0.000	1.895
C4	0.000	0.000	-1.895
H5	0.000	0.000	2.960
H6	0.000	0.000	-2.960

	C1	C2	C3	C4	H5	H6
C1		1.3605	1.2143	2.5749	2.2797	3.6402
C2	1.3605		2.5749	1.2143	3.6402	2.2797
C3	1.2143	2.5749		3.7892	1.0654	4.8546
C4	2.5749	1.2143	3.7892		4.8546	1.0654
H5	2.2797	3.6402	1.0654	4.8546		5.9200
H6	3.6402	2.2797	4.8546	1.0654	5.9200

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: B97D3/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	0.802
2	C	0.802
3	C	-0.888
4	C	-0.888
5	H	0.086
6	H	0.086

<r²>	78.976
(<r²>)^1/2	8.887

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B97D3/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)