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	hartrees
Energy at 0K	-153.265448
Energy at 298.15K	-153.264616
HF Energy	-152.548899
Nuclear repulsion energy	76.958792

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3464	3336
2	Σ_g	2194	2113
3	Σ_g	887	854
4	Σ_u	3443	3316
5	Σ_u	2008	1933
6	Π_g	631	608
6	Π_g	631	608
7	Π_g	486	468
7	Π_g	486	468
8	Π_u	659	635
8	Π_u	659	635
9	Π_u	240	231
9	Π_u	240	231

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.683
C2	0.000	0.000	-0.683
C3	0.000	0.000	1.899
C4	0.000	0.000	-1.899
H5	0.000	0.000	2.959
H6	0.000	0.000	-2.959

	C1	C2	C3	C4	H5	H6
C1		1.3661	1.2163	2.5825	2.2758	3.6420
C2	1.3661		2.5825	1.2163	3.6420	2.2758
C3	1.2163	2.5825		3.7988	1.0595	4.8583
C4	2.5825	1.2163	3.7988		4.8583	1.0595
H5	2.2758	3.6420	1.0595	4.8583		5.9178
H6	3.6420	2.2758	4.8583	1.0595	5.9178

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=FULL/cc-pVTZ

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=FULL/cc-pVTZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)