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	hartrees
Energy at 0K	-153.038390
Energy at 298.15K
HF Energy	-152.491249
Nuclear repulsion energy	76.263927

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3474	3317
2	Σ_g	2208	2108
3	Σ_g	897	856
4	Σ_u	3475	3318
5	Σ_u	2024	1933
6	Π_g	581	554
6	Π_g	581	554
7	Π_g	112i	107i
7	Π_g	112i	107i
8	Π_u	415	397
8	Π_u	415	397
9	Π_u	209	200
9	Π_u	209	200

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.690
C2	0.000	0.000	-0.690
C3	0.000	0.000	1.917
C4	0.000	0.000	-1.917
H5	0.000	0.000	2.987
H6	0.000	0.000	-2.987

	C1	C2	C3	C4	H5	H6
C1		1.3804	1.2264	2.6068	2.2968	3.6772
C2	1.3804		2.6068	1.2264	3.6772	2.2968
C3	1.2264	2.6068		3.8332	1.0704	4.9036
C4	2.6068	1.2264	3.8332		4.9036	1.0704
H5	2.2968	3.6772	1.0704	4.9036		5.9740
H6	3.6772	2.2968	4.9036	1.0704	5.9740

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: MP4/6-31G*

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: MP4/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)