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	hartrees
Energy at 0K	-77.201561
Energy at 298.15K	-77.201712
HF Energy	-76.849783
Nuclear repulsion energy	24.862450

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3558	3374	0.00
2	Σ_g	2063	1956	0.00
3	Σ_u	3430	3252	84.57
4	Π_g	634	601	0.00
4	Π_g	634	601	0.00
5	Π_u	775	734	90.65
5	Π_u	775	734	90.65

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.657
H4	0.000	0.000	-1.657

	C1	C2	H3	H4
C1		1.1995	1.0572	2.2567
C2	1.1995		2.2567	1.0572
H3	1.0572	2.2567		3.3139
H4	2.2567	1.0572	3.3139

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD=FULL/cc-pVTZ

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=FULL/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)