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	hartrees
Energy at 0K	-77.098117
Energy at 298.15K	-77.098032
HF Energy	-76.825127
Nuclear repulsion energy	24.536239

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	3580	3362	0.00	73.39	0.22	0.36
2	Σ_g	1989	1868	0.00	58.09	0.11	0.20
3	Σ_u	3490	3277	90.31	0.00	0.00	0.00
4	Π_g	478	449	0.00	7.17	0.75	0.86
4	Π_g	478	449	0.00	7.17	0.75	0.86
5	Π_u	748	702	111.67	0.00	0.00	0.00
5	Π_u	748	702	111.67	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.610
C2	0.000	0.000	-0.610
H3	0.000	0.000	1.673
H4	0.000	0.000	-1.673

	C1	C2	H3	H4
C1		1.2195	1.0629	2.2824
C2	1.2195		2.2824	1.0629
H3	1.0629	2.2824		3.3453
H4	2.2824	1.0629	3.3453

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/6-31+G**

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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HF vs MP2 Bad vib. Calc. vs exp. 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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: MP2=FULL/6-31+G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)