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	hartrees
Energy at 0K	-12.399603
Energy at 298.15K	-12.399828
HF Energy	-12.399603
Nuclear repulsion energy	12.903344

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3492	3403	0.00
2	Σ_g	1995	1944	0.00
3	Σ_u	3380	3294	72.90
4	Π_g	687	669	0.00
4	Π_g	687	669	0.00
5	Π_u	799	779	141.14
5	Π_u	799	779	141.14

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	1.678
H4	0.000	0.000	-1.678

	C1	C2	H3	H4
C1		1.2217	1.0674	2.2891
C2	1.2217		2.2891	1.0674
H3	1.0674	2.2891		3.3565
H4	2.2891	1.0674	3.3565

Number	Element	Mulliken
1	C	-0.288
2	C	-0.288
3	H	0.288
4	H	0.288

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3LYPultrafine/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>	15.690
(<r²>)^1/2	3.961

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3LYPultrafine/CEP-121G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)