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	hartrees
Energy at 0K	-153.118270
Energy at 298.15K	-153.116166
HF Energy	-152.544120
Nuclear repulsion energy	76.599480

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3483	3354
2	Σ_g	2188	2106
3	Σ_g	888	855
4	Σ_u	3484	3355
5	Σ_u	2007	1932
6	Π_g	554	534
6	Π_g	554	534
7	Π_g	160	154
7	Π_g	160	154
8	Π_u	521	502
8	Π_u	521	502
9	Π_u	157	151
9	Π_u	157	151

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.687
C2	0.000	0.000	-0.687
C3	0.000	0.000	1.909
C4	0.000	0.000	-1.909
H5	0.000	0.000	2.973
H6	0.000	0.000	-2.973

	C1	C2	C3	C4	H5	H6
C1		1.3749	1.2211	2.5960	2.2852	3.6601
C2	1.3749		2.5960	1.2211	3.6601	2.2852
C3	1.2211	2.5960		3.8170	1.0641	4.8812
C4	2.5960	1.2211	3.8170		4.8812	1.0641
H5	2.2852	3.6601	1.0641	4.8812		5.9453
H6	3.6601	2.2852	4.8812	1.0641	5.9453

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/TZVP

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/TZVP

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)