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	hartrees
Energy at 0K	-76.594097
Energy at 298.15K	-76.594088
HF Energy	-76.393474
Nuclear repulsion energy	24.521455

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3479	3344	0.00
2	Σ_g	2012	1934	0.00
3	Σ_u	3375	3244	62.23
4	Π_g	536	516	0.00
4	Π_g	536	516	0.00
5	Π_u	735	706	93.72
5	Π_u	735	706	93.72

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	1.678
H4	0.000	0.000	-1.678

	C1	C2	H3	H4
C1		1.2177	1.0686	2.2864
C2	1.2177		2.2864	1.0686
H3	1.0686	2.2864		3.3550
H4	2.2864	1.0686	3.3550

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD/3-21G*

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/3-21G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)