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	hartrees
Energy at 0K	-77.164517
Energy at 298.15K	-77.164593
HF Energy	-76.849184
Nuclear repulsion energy	24.645341

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3528	3528	0.00	68.24	0.20	0.33
2	Σ_g	1967	1967	0.00	89.50	0.06	0.10
3	Σ_u	3430	3430	95.69	0.00	0.00	0.00
4	Π_g	593	593	0.00	2.14	0.75	0.86
4	Π_g	593	593	0.00	2.14	0.75	0.86
5	Π_u	746	746	89.18	0.00	0.63	0.00
5	Π_u	746	746	89.18	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.606
C2	0.000	0.000	-0.606
H3	0.000	0.000	1.668
H4	0.000	0.000	-1.668

	C1	C2	H3	H4
C1		1.2122	1.0620	2.2742
C2	1.2122		2.2742	1.0620
H3	1.0620	2.2742		3.3362
H4	2.2742	1.0620	3.3362

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/daug-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: MP2/daug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)