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	hartrees
Energy at 0K	-77.213961
Energy at 298.15K	-77.214129
HF Energy	-76.848235
Nuclear repulsion energy	24.811780

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3537	3537	0.00
2	Σ_g	2049	2049	0.00
3	Σ_u	3438	3438	84.40
4	Π_g	652	652	0.00
4	Π_g	652	652	0.00
5	Π_u	774	774	93.25
5	Π_u	774	774	93.25

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.2007	1.0619	2.2626
C2	1.2007		2.2626	1.0619
H3	1.0619	2.2626		3.3246
H4	2.2626	1.0619	3.3246

All results from a given calculation for C₂H₂ (Acetylene)

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

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)