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	hartrees
Energy at 0K	-77.089614
Energy at 298.15K	-77.089604
HF Energy	-76.834223
Nuclear repulsion energy	24.777486

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3566	3300	0.00
2	Σ_g	2081	1926	0.00
3	Σ_u	3463	3204	73.98
4	Π_g	512	474	0.00
4	Π_g	512	474	0.00
5	Π_u	775	717	102.51
5	Π_u	775	717	102.51

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.601
C2	0.000	0.000	-0.601
H3	0.000	0.000	1.665
H4	0.000	0.000	-1.665

	C1	C2	H3	H4
C1		1.2023	1.0635	2.2658
C2	1.2023		2.2658	1.0635
H3	1.0635	2.2658		3.3293
H4	2.2658	1.0635	3.3293

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CISD/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 C2H2 (Acetylene)

using model chemistry: CISD/6-311G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)