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	hartrees
Energy at 0K	-152.567180
Energy at 298.15K	-152.566637
HF Energy	-152.567180
Nuclear repulsion energy	76.833703

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3404	3353	0.00
2	Σ_g	2258	2224	0.00
3	Σ_g	935	921	0.00
4	Σ_u	3405	3354	239.29
5	Σ_u	2067	2036	4.52
6	Π_g	777	766	0.00
6	Π_g	777	766	0.00
7	Π_g	589	580	0.00
7	Π_g	589	580	0.00
8	Π_u	608	599	129.71
8	Π_u	608	599	129.71
9	Π_u	270	266	13.13
9	Π_u	270	266	13.13

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.677
C2	0.000	0.000	-0.677
C3	0.000	0.000	1.899
C4	0.000	0.000	-1.899
H5	0.000	0.000	2.976
H6	0.000	0.000	-2.976

	C1	C2	C3	C4	H5	H6
C1		1.3548	1.2219	2.5768	2.2985	3.6533
C2	1.3548		2.5768	1.2219	3.6533	2.2985
C3	1.2219	2.5768		3.7987	1.0766	4.8753
C4	2.5768	1.2219	3.7987		4.8753	1.0766
H5	2.2985	3.6533	1.0766	4.8753		5.9519
H6	3.6533	2.2985	4.8753	1.0766	5.9519

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: LSDA/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	0.525
2	C	0.525
3	C	-0.808
4	C	-0.808
5	H	0.283
6	H	0.283

<r²>	79.260
(<r²>)^1/2	8.903

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: LSDA/6-31+G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)