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	hartrees
Energy at 0K	-77.170941
Energy at 298.15K	-77.171073
HF Energy	-76.848219
Nuclear repulsion energy	24.776533

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3520	3520	0.00
2	Σ_g	2042	2042	0.00
3	Σ_u	3421	3421	84.23
4	Π_g	628	628	0.00
4	Π_g	628	628	0.00
5	Π_u	765	765	92.28
5	Π_u	765	765	92.28

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.601
C2	0.000	0.000	-0.601
H3	0.000	0.000	1.664
H4	0.000	0.000	-1.664

	C1	C2	H3	H4
C1		1.2027	1.0628	2.2655
C2	1.2027		2.2655	1.0628
H3	1.0628	2.2655		3.3283
H4	2.2655	1.0628	3.3283

All results from a given calculation for C₂H₂ (Acetylene)

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

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)