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	hartrees
Energy at 0K	-77.173178
Energy at 298.15K	-77.173350
HF Energy	-76.850447
Nuclear repulsion energy	24.829626

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3559	3559	0.00
2	Σ_g	2083	2083	0.00
3	Σ_u	3443	3443	88.77
4	Π_g	649	649	0.00
4	Π_g	649	649	0.00
5	Π_u	780	780	93.95
5	Π_u	780	780	93.95

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	1.661
H4	0.000	0.000	-1.661

	C1	C2	H3	H4
C1		1.2001	1.0605	2.2607
C2	1.2001		2.2607	1.0605
H3	1.0605	2.2607		3.3212
H4	2.2607	1.0605	3.3212

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP3/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: MP3/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)