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	hartrees
Energy at 0K	-152.550373
Energy at 298.15K	-152.550023
HF Energy	-152.550373
Nuclear repulsion energy	77.909777

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3626	3295	0.00
2	Σ_g	2487	2260	0.00
3	Σ_g	933	848	0.00
4	Σ_u	3626	3294	189.46
5	Σ_u	2294	2084	1.44
6	Π_g	819	744	0.00
6	Π_g	819	744	0.00
7	Π_g	585	532	0.00
7	Π_g	585	532	0.00
8	Π_u	825	750	101.94
8	Π_u	825	750	101.94
9	Π_u	257	234	12.92
9	Π_u	257	234	12.92

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.692
C2	0.000	0.000	-0.692
C3	0.000	0.000	1.875
C4	0.000	0.000	-1.875
H5	0.000	0.000	2.930
H6	0.000	0.000	-2.930

	C1	C2	C3	C4	H5	H6
C1		1.3849	1.1828	2.5676	2.2377	3.6226
C2	1.3849		2.5676	1.1828	3.6226	2.2377
C3	1.1828	2.5676		3.7504	1.0550	4.8053
C4	2.5676	1.1828	3.7504		4.8053	1.0550
H5	2.2377	3.6226	1.0550	4.8053		5.8603
H6	3.6226	2.2377	4.8053	1.0550	5.8603

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: HF/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: HF/TZVP

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)