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	hartrees
Energy at 0K	-77.167138
Energy at 298.15K	-77.166806
HF Energy	-76.848047
Nuclear repulsion energy	24.768720

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3552	3365	0.00
2	Σ_g	2056	1948	0.00
3	Σ_u	3454	3272	80.32
4	Π_g	345	327	0.00
4	Π_g	345	327	0.00
5	Π_u	747	708	100.82
5	Π_u	747	708	100.82

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.664
H4	0.000	0.000	-1.664

	C1	C2	H3	H4
C1		1.2035	1.0622	2.2657
C2	1.2035		2.2657	1.0622
H3	1.0622	2.2657		3.3279
H4	2.2657	1.0622	3.3279

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD=FULL/TZVP

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/TZVP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)