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	hartrees
Energy at 0K	-77.168300
Energy at 298.15K	-77.168451
HF Energy	-76.849555
Nuclear repulsion energy	24.804727

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3543	3308	0.00
2	Σ_g	2064	1927	0.00
3	Σ_u	3435	3207	85.80
4	Π_g	634	592	0.00
4	Π_g	634	592	0.00
5	Π_u	773	721	91.47
5	Π_u	773	721	91.47

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	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.2012	1.0619	2.2631
C2	1.2012		2.2631	1.0619
H3	1.0619	2.2631		3.3250
H4	2.2631	1.0619	3.3250

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCD/cc-pVTZ

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: CCD/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)