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	hartrees
Energy at 0K	-77.083446
Energy at 298.15K	-77.083252
HF Energy	-76.815949
Nuclear repulsion energy	24.591305

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3537	3368	0.00
2	Σ_g	2052	1954	0.00
3	Σ_u	3440	3276	68.32
4	Π_g	418	398	0.00
4	Π_g	418	398	0.00
5	Π_u	751	716	87.34
5	Π_u	751	716	87.34

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.606
C2	0.000	0.000	-0.606
H3	0.000	0.000	1.675
H4	0.000	0.000	-1.675

	C1	C2	H3	H4
C1		1.2126	1.0691	2.2817
C2	1.2126		2.2817	1.0691
H3	1.0691	2.2817		3.3507
H4	2.2817	1.0691	3.3507

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD/6-31G*

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/6-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)