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	hartrees
Energy at 0K	-77.144842
Energy at 298.15K	-77.145059
HF Energy	-76.848682
Nuclear repulsion energy	24.903037

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3577	3297	0.00
2	Σ_g	2096	1933	0.00
3	Σ_u	3475	3203	90.60
4	Π_g	685	632	0.00
4	Π_g	685	632	0.00
5	Π_u	796	734	97.01
5	Π_u	796	734	97.01

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.598
C2	0.000	0.000	-0.598
H3	0.000	0.000	1.657
H4	0.000	0.000	-1.657

	C1	C2	H3	H4
C1		1.1955	1.0597	2.2552
C2	1.1955		2.2552	1.0597
H3	1.0597	2.2552		3.3148
H4	2.2552	1.0597	3.3148

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CISD/6-311+G(3df,2p)

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/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)