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	hartrees
Energy at 0K	-77.185735
Energy at 298.15K	-77.185844
HF Energy	-76.853876
Nuclear repulsion energy	24.693681

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	3530	3353	0.00	67.90	0.20	0.33
2	Σ_g	1975	1876	0.00	88.17	0.06	0.11
3	Σ_u	3443	3269	95.52	0.00	0.00	0.00
4	Π_g	614	583	0.00	2.13	0.75	0.86
4	Π_g	614	583	0.00	2.13	0.75	0.86
5	Π_u	750	713	89.02	0.00	0.72	0.84
5	Π_u	750	713	89.02	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.605
C2	0.000	0.000	-0.605
H3	0.000	0.000	1.666
H4	0.000	0.000	-1.666

	C1	C2	H3	H4
C1		1.2091	1.0614	2.2705
C2	1.2091		2.2705	1.0614
H3	1.0614	2.2705		3.3319
H4	2.2705	1.0614	3.3319

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/aug-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: MP2/aug-cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)