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	hartrees
Energy at 0K	-77.270741
Energy at 298.15K	-77.270610
HF Energy	-77.270741
Nuclear repulsion energy	24.572315

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	3486	3418	0.00	67.61	0.22	0.36
2	Σ_g	2036	1996	0.00	49.73	0.26	0.41
3	Σ_u	3390	3324	59.90	0.00	0.00	0.00
4	Π_g	455	446	0.00	1.30	0.75	0.86
4	Π_g	455	446	0.00	1.30	0.75	0.86
5	Π_u	748	733	80.70	0.00	0.00	0.00
5	Π_u	748	733	80.70	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.607
C2	0.000	0.000	-0.607
H3	0.000	0.000	1.677
H4	0.000	0.000	-1.677

	C1	C2	H3	H4
C1		1.2132	1.0707	2.2838
C2	1.2132		2.2838	1.0707
H3	1.0707	2.2838		3.3545
H4	2.2838	1.0707	3.3545

Number	Element	Mulliken
1	C	-0.190
2	C	-0.190
3	H	0.190
4	H	0.190

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B97D3/6-31G*

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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<r²>	16.851
(<r²>)^1/2	4.105

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B97D3/6-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)