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	hartrees
Energy at 0K	-153.107949
Energy at 298.15K
HF Energy	-152.528106
Nuclear repulsion energy	76.312593

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3471	3366
2	Σ_g	2175	2109
3	Σ_g	882	856
4	Σ_u	3471	3366
5	Σ_u	1986	1926
6	Π_g	609	591
6	Π_g	609	591
7	Π_g	187i	182i
7	Π_g	187i	182i
8	Π_u	587	570
8	Π_u	587	570
9	Π_u	200	193
9	Π_u	200	193

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	1.916
C4	0.000	0.000	-1.916
H5	0.000	0.000	2.983
H6	0.000	0.000	-2.983

	C1	C2	C3	C4	H5	H6
C1		1.3804	1.2257	2.6061	2.2930	3.6734
C2	1.3804		2.6061	1.2257	3.6734	2.2930
C3	1.2257	2.6061		3.8318	1.0673	4.8990
C4	2.6061	1.2257	3.8318		4.8990	1.0673
H5	2.2930	3.6734	1.0673	4.8990		5.9663
H6	3.6734	2.2930	4.8990	1.0673	5.9663

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: MP4/6-311G**

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: MP4/6-311G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)