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	hartrees
Energy at 0K	-153.084726
Energy at 298.15K
HF Energy	-152.505275
Nuclear repulsion energy	75.633241

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3451	3365
2	Σ_g	2164	2110
3	Σ_g	883	861
4	Σ_u	3451	3365
5	Σ_u	1977	1928
6	Π_g	543	529
6	Π_g	543	529
7	Π_g	648i	632i
7	Π_g	648i	632i
8	Π_u	504	492
8	Π_u	504	492
9	Π_u	127	124
9	Π_u	127	124

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.695
C2	0.000	0.000	-0.695
C3	0.000	0.000	1.933
C4	0.000	0.000	-1.933
H5	0.000	0.000	3.010
H6	0.000	0.000	-3.010

	C1	C2	C3	C4	H5	H6
C1		1.3891	1.2386	2.6277	2.3152	3.7043
C2	1.3891		2.6277	1.2386	3.7043	2.3152
C3	1.2386	2.6277		3.8663	1.0766	4.9428
C4	2.6277	1.2386	3.8663		4.9428	1.0766
H5	2.3152	3.7043	1.0766	4.9428		6.0194
H6	3.7043	2.3152	4.9428	1.0766	6.0194

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/aug-cc-pVDZ

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/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)