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	hartrees
Energy at 0K	-76.835144
Energy at 298.15K	-76.835462
HF Energy	-76.835144
Nuclear repulsion energy	25.117512

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	3686	3334	0.00	42.90	0.30	0.46
2	Σ_g	2214	2002	0.00	71.83	0.22	0.36
3	Σ_u	3573	3232	74.91	0.00	0.00	0.00
4	Π_g	765	692	0.00	7.33	0.75	0.86
4	Π_g	765	692	0.00	7.33	0.75	0.86
5	Π_u	860	778	111.62	0.00	0.00	0.00
5	Π_u	860	778	111.62	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.591
C2	0.000	0.000	-0.591
H3	0.000	0.000	1.647
H4	0.000	0.000	-1.647

	C1	C2	H3	H4
C1		1.1829	1.0556	2.2385
C2	1.1829		2.2385	1.0556
H3	1.0556	2.2385		3.2942
H4	2.2385	1.0556	3.2942

Number	Element	Mulliken
1	C	-0.272
2	C	-0.272
3	H	0.272
4	H	0.272

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HF/6-311G*

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>	16.714
(<r²>)^1/2	4.088

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HF/6-311G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)