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	hartrees
Energy at 0K	-77.305439
Energy at 298.15K	-77.305529
HF Energy	-77.305439
Nuclear repulsion energy	24.725553

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	3462	3417	0.00	56.42	0.28	0.44
2	Σ_g	2013	1987	0.00	109.52	0.07	0.13
3	Σ_u	3366	3323	75.14	0.00	0.00	0.00
4	Π_g	603	595	0.00	3.97	0.75	0.86
4	Π_g	603	595	0.00	3.97	0.75	0.86
5	Π_u	742	733	98.40	0.00	0.00	0.00
5	Π_u	742	733	98.40	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.669
H4	0.000	0.000	-1.669

	C1	C2	H3	H4
C1		1.2045	1.0663	2.2709
C2	1.2045		2.2709	1.0663
H3	1.0663	2.2709		3.3372
H4	2.2709	1.0663	3.3372

Number	Element	Mulliken
1	C	-0.211
2	C	-0.211
3	H	0.211
4	H	0.211

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B97D3/6-311+G(3df,2p)

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>	17.112
(<r²>)^1/2	4.137

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B97D3/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)