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	hartrees
Energy at 0K	-153.204969
Energy at 298.15K	-153.199952
HF Energy	-152.497928
Nuclear repulsion energy	77.643789

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3665	3453	0.00
2	Σ_g	2507	2362	0.00
3	Σ_g	943	888	0.00
4	Σ_u	3665	3453	151.14
5	Σ_u	2313	2179	0.02
6	Π_g	888	837	0.00
6	Π_g	888	837	0.00
7	Π_g	681	642	0.00
7	Π_g	681	642	0.00
8	Π_u	823	776	107.59
8	Π_u	823	776	107.59
9	Π_u	280	264	8.36
9	Π_u	280	264	8.36

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.686
C2	0.000	0.000	-0.686
C3	0.000	0.000	1.910
C4	0.000	0.000	-1.910
H5	0.000	0.000	2.976
H6	0.000	0.000	-2.976

	C1	C2	C3	C4	H5	H6
C1		1.3728	1.2231	2.5959	2.2900	3.6627
C2	1.3728		2.5959	1.2231	3.6627	2.2900
C3	1.2231	2.5959		3.8190	1.0668	4.8859
C4	2.5959	1.2231	3.8190		4.8859	1.0668
H5	2.2900	3.6627	1.0668	4.8859		5.9527
H6	3.6627	2.2900	4.8859	1.0668	5.9527

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: G2

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: G2

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)