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	hartrees
Energy at 0K	-77.172489
Energy at 298.15K	-77.172654
HF Energy	-76.850281
Nuclear repulsion energy	24.797524

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3536	3384	0.00
2	Σ_g	2058	1970	0.00
3	Σ_u	3420	3273	85.29
4	Π_g	646	618	0.00
4	Π_g	646	618	0.00
5	Π_u	774	741	91.58
5	Π_u	774	741	91.58

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	1.663
H4	0.000	0.000	-1.663

	C1	C2	H3	H4
C1		1.2016	1.0620	2.2636
C2	1.2016		2.2636	1.0620
H3	1.0620	2.2636		3.3257
H4	2.2636	1.0620	3.3257

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCD/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: CCD/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)