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	hartrees
Energy at 0K	-12.412524
Energy at 298.15K	-12.412400
HF Energy	-12.412524
Nuclear repulsion energy	12.854965

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3423	3423	0.00
2	Σ_g	1975	1975	0.00
3	Σ_u	3327	3327	69.32
4	Π_g	455	455	0.00
4	Π_g	455	455	0.00
5	Π_u	748	748	111.49
5	Π_u	748	748	111.49

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.611
C2	0.000	0.000	-0.611
H3	0.000	0.000	1.689
H4	0.000	0.000	-1.689

	C1	C2	H3	H4
C1		1.2216	1.0782	2.2998
C2	1.2216		2.2998	1.0782
H3	1.0782	2.2998		3.3780
H4	2.2998	1.0782	3.3780

Number	Element	Mulliken
1	C	-0.298
2	C	-0.298
3	H	0.298
4	H	0.298

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/CEP-121G*

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>	15.664
(<r²>)^1/2	3.958

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/CEP-121G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)