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	hartrees
Energy at 0K	-77.188733
Energy at 298.15K	-77.188897
HF Energy	-76.854867
Nuclear repulsion energy	24.854966

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3534	3534	0.00
2	Σ_g	2069	2069	0.00
3	Σ_u	3435	3435	85.68
4	Π_g	650	650	0.00
4	Π_g	650	650	0.00
5	Π_u	772	772	92.17
5	Π_u	772	772	92.17

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.599
C2	0.000	0.000	-0.599
H3	0.000	0.000	1.660
H4	0.000	0.000	-1.660

	C1	C2	H3	H4
C1		1.1979	1.0615	2.2594
C2	1.1979		2.2594	1.0615
H3	1.0615	2.2594		3.3209
H4	2.2594	1.0615	3.3209

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCD/cc-pVQZ

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-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)