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	hartrees
Energy at 0K	-77.233742
Energy at 298.15K	-77.233835
HF Energy	-76.847710
Nuclear repulsion energy	24.704658

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3504	3504
2	Σ_g	2000	2000
3	Σ_u	3410	3410
4	Π_g	604	604
4	Π_g	604	604
5	Π_u	749	749
5	Π_u	748	748

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.604
C2	0.000	0.000	-0.604
H3	0.000	0.000	1.667
H4	0.000	0.000	-1.667

	C1	C2	H3	H4
C1		1.2073	1.0632	2.2705
C2	1.2073		2.2705	1.0632
H3	1.0632	2.2705		3.3338
H4	2.2705	1.0632	3.3338

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD(T)=FULL/6-311+G(3df,2pd)

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: CCSD(T)=FULL/6-311+G(3df,2pd)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)