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	hartrees
Energy at 0K	-77.249113
Energy at 298.15K	-77.249270
HF Energy	-76.854939
Nuclear repulsion energy	24.874930

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3535	3535	0.00
2	Σ_g	2060	2060	0.00
3	Σ_u	3437	3437	84.77
4	Π_g	639	639	0.00
4	Π_g	639	639	0.00
5	Π_u	777	777	91.82
5	Π_u	777	777	91.82

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.599
C2	0.000	0.000	-0.599
H3	0.000	0.000	1.658
H4	0.000	0.000	-1.658

	C1	C2	H3	H4
C1		1.1975	1.0595	2.2570
C2	1.1975		2.2570	1.0595
H3	1.0595	2.2570		3.3165
H4	2.2570	1.0595	3.3165

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD=FULL/cc-pVQZ

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-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)