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	hartrees
Energy at 0K	-12.227592
Energy at 298.15K	-12.227119
HF Energy	-12.027796
Nuclear repulsion energy	12.755610

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3401	3244	0.00
2	Σ_g	1906	1818	0.00
3	Σ_u	3299	3146	45.21
4	Π_g	290	277	0.00
4	Π_g	290	277	0.00
5	Π_u	723	689	114.80
5	Π_u	723	689	114.80

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.619
C2	0.000	0.000	-0.619
H3	0.000	0.000	1.695
H4	0.000	0.000	-1.695

	C1	C2	H3	H4
C1		1.2385	1.0761	2.3146
C2	1.2385		2.3146	1.0761
H3	1.0761	2.3146		3.3907
H4	2.3146	1.0761	3.3907

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)