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	hartrees
Energy at 0K	-152.999037
Energy at 298.15K	-152.997657
HF Energy	-152.495732
Nuclear repulsion energy	76.836339

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3532	3315	0.00
2	Σ_g	2363	2218	0.00
3	Σ_g	917	860	0.00
4	Σ_u	3533	3316	146.10
5	Σ_u	2175	2041	0.01
6	Π_g	615	577	0.00
6	Π_g	615	577	0.00
7	Π_g	313	294	0.00
7	Π_g	313	294	0.00
8	Π_u	519	487	106.15
8	Π_u	519	487	106.15
9	Π_u	244	229	1.21
9	Π_u	244	229	1.21

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.692
C2	0.000	0.000	-0.692
C3	0.000	0.000	1.902
C4	0.000	0.000	-1.902
H5	0.000	0.000	2.968
H6	0.000	0.000	-2.968

	C1	C2	C3	C4	H5	H6
C1		1.3849	1.2092	2.5940	2.2756	3.6605
C2	1.3849		2.5940	1.2092	3.6605	2.2756
C3	1.2092	2.5940		3.8032	1.0664	4.8696
C4	2.5940	1.2092	3.8032		4.8696	1.0664
H5	2.2756	3.6605	1.0664	4.8696		5.9361
H6	3.6605	2.2756	4.8696	1.0664	5.9361

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: MP3/6-31G*

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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All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: MP3/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)