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	hartrees
Energy at 0K	-77.098264
Energy at 298.15K	-77.098044
HF Energy	-76.825380
Nuclear repulsion energy	24.302143

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	3527	3418	0.00	73.85	0.20	0.34
2	Σ_g	1950	1890	0.00	83.05	0.07	0.14
3	Σ_u	3436	3331	93.58	0.00	0.00	0.00
4	Π_g	414	401	0.00	2.65	0.75	0.86
4	Π_g	414	401	0.00	2.65	0.75	0.86
5	Π_u	708	686	94.47	0.00	0.00	0.00
5	Π_u	708	686	94.47	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.615
C2	0.000	0.000	-0.615
H3	0.000	0.000	1.690
H4	0.000	0.000	-1.690

	C1	C2	H3	H4
C1		1.2306	1.0744	2.3050
C2	1.2306		2.3050	1.0744
H3	1.0744	2.3050		3.3795
H4	2.3050	1.0744	3.3795

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/aug-cc-pVDZ

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/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)