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	hartrees
Energy at 0K	-23.211286
Energy at 298.15K	-23.209451
HF Energy	-22.871316
Nuclear repulsion energy	35.319416

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3454	3338	0.00
2	Σ_g	2144	2072	0.00
3	Σ_g	857	828	0.00
4	Σ_u	3454	3338	103.92
5	Σ_u	1919	1854	0.67
6	Π_g	637	616	0.00
6	Π_g	637	616	0.00
7	Π_g	131	127	0.00
7	Π_g	131	127	0.00
8	Π_u	630	609	157.93
8	Π_u	630	609	157.93
9	Π_u	209	202	3.86
9	Π_u	209	202	3.86

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.713
C2	0.000	0.000	-0.713
C3	0.000	0.000	1.993
C4	0.000	0.000	-1.993
H5	0.000	0.000	3.069
H6	0.000	0.000	-3.069

	C1	C2	C3	C4	H5	H6
C1		1.4255	1.2806	2.7061	2.3561	3.7816
C2	1.4255		2.7061	1.2806	3.7816	2.3561
C3	1.2806	2.7061		3.9866	1.0756	5.0622
C4	2.7061	1.2806	3.9866		5.0622	1.0756
H5	2.3561	3.7816	1.0756	5.0622		6.1377
H6	3.7816	2.3561	5.0622	1.0756	6.1377

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/CEP-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/CEP-31G

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)