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	hartrees
Energy at 0K	-153.038766
Energy at 298.15K
HF Energy	-152.505672
Nuclear repulsion energy	75.825268

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3485	3377	0.00
2	Σ_g	2179	2112	0.00
3	Σ_g	898	870	0.00
4	Σ_u	3484	3377	166.55
5	Σ_u	1984	1923	1.26
6	Π_g	559	542	0.00
6	Π_g	559	542	0.00
7	Π_g	636i	616i	0.00
7	Π_g	636i	616i	0.00
8	Π_u	525	509	86.14
8	Π_u	525	509	86.14
9	Π_u	161	156	2.67
9	Π_u	161	156	2.67

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	1.928
C4	0.000	0.000	-1.928
H5	0.000	0.000	3.002
H6	0.000	0.000	-3.002

	C1	C2	C3	C4	H5	H6
C1		1.3810	1.2377	2.6187	2.3114	3.6924
C2	1.3810		2.6187	1.2377	3.6924	2.3114
C3	1.2377	2.6187		3.8564	1.0737	4.9301
C4	2.6187	1.2377	3.8564		4.9301	1.0737
H5	2.3114	3.6924	1.0737	4.9301		6.0038
H6	3.6924	2.3114	4.9301	1.0737	6.0038

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: MP2=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: MP2=FULL/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)