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	hartrees
Energy at 0K	-12.014790
Energy at 298.15K	-12.015182
Nuclear repulsion energy	12.907285

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3732	3364	0.00
2	Σ_g	2178	1963	0.00
3	Σ_u	3601	3246	96.43
4	Π_g	827	745	0.00
4	Π_g	827	745	0.00
5	Π_u	929	837	151.74
5	Π_u	929	837	151.74

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.614
C2	0.000	0.000	-0.614
H3	0.000	0.000	1.672
H4	0.000	0.000	-1.672

	C1	C2	H3	H4
C1		1.2274	1.0586	2.2860
C2	1.2274		2.2860	1.0586
H3	1.0586	2.2860		3.3446
H4	2.2860	1.0586	3.3446

Number	Element	Mulliken
1	C	-0.361
2	C	-0.361
3	H	0.361
4	H	0.361

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HF/CEP-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>	15.823
(<r²>)^1/2	3.978

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HF/CEP-31G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)