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	hartrees
Energy at 0K	-77.210482
Energy at 298.15K	-77.210672
HF Energy	-76.850533
Nuclear repulsion energy	24.865198

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3567	3392	0.00
2	Σ_g	2060	1959	0.00
3	Σ_u	3399	3232	84.17
4	Π_g	673	640	0.00
4	Π_g	673	640	0.00
5	Π_u	773	735	90.94
5	Π_u	773	735	90.94

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	1.656
H4	0.000	0.000	-1.656

	C1	C2	H3	H4
C1		1.1998	1.0562	2.2560
C2	1.1998		2.2560	1.0562
H3	1.0562	2.2560		3.3121
H4	2.2560	1.0562	3.3121

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD=FULL/aug-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/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)