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	hartrees
Energy at 0K	-152.992797
Energy at 298.15K	-152.991066
HF Energy	-152.491850
Nuclear repulsion energy	76.450707

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3515	3315	0.00
2	Σ_g	2227	2100	0.00
3	Σ_g	908	856	0.00
4	Σ_u	3516	3315	157.03
5	Σ_u	2035	1919	0.37
6	Π_g	597	563	0.00
6	Π_g	597	563	0.00
7	Π_g	241	227	0.00
7	Π_g	241	227	0.00
8	Π_u	451	425	102.61
8	Π_u	451	425	102.61
9	Π_u	231	218	0.06
9	Π_u	231	218	0.06

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.689
C2	0.000	0.000	-0.689
C3	0.000	0.000	1.914
C4	0.000	0.000	-1.914
H5	0.000	0.000	2.981
H6	0.000	0.000	-2.981

	C1	C2	C3	C4	H5	H6
C1		1.3776	1.2249	2.6025	2.2923	3.6700
C2	1.3776		2.6025	1.2249	3.6700	2.2923
C3	1.2249	2.6025		3.8274	1.0675	4.8949
C4	2.6025	1.2249	3.8274		4.8949	1.0675
H5	2.2923	3.6700	1.0675	4.8949		5.9623
H6	3.6700	2.2923	4.8949	1.0675	5.9623

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: MP2/6-31G*

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: MP2/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)