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	hartrees
Energy at 0K	-12.330041
Energy at 298.15K	-12.329732
HF Energy	-12.061666
Nuclear repulsion energy	12.901315

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3488	3326	0.00
2	Σ_g	1994	1902	0.00
3	Σ_u	3394	3237	61.44
4	Π_g	352	335	0.00
4	Π_g	352	335	0.00
5	Π_u	767	731	110.64
5	Π_u	767	731	110.64

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.681
H4	0.000	0.000	-1.681

	C1	C2	H3	H4
C1		1.2189	1.0718	2.2908
C2	1.2189		2.2908	1.0718
H3	1.0718	2.2908		3.3626
H4	2.2908	1.0718	3.3626

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD/CEP-121G*

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: QCISD/CEP-121G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)