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	hartrees
Energy at 0K	-12.398127
Energy at 298.15K	-12.398226
HF Energy	-12.398127
Nuclear repulsion energy	12.804461

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3428	3428	0.00
2	Σ_g	1948	1948	0.00
3	Σ_u	3319	3319	69.21
4	Π_g	593	593	0.00
4	Π_g	593	593	0.00
5	Π_u	762	762	133.02
5	Π_u	762	762	133.02

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.616
C2	0.000	0.000	-0.616
H3	0.000	0.000	1.691
H4	0.000	0.000	-1.691

	C1	C2	H3	H4
C1		1.2311	1.0758	2.3069
C2	1.2311		2.3069	1.0758
H3	1.0758	2.3069		3.3827
H4	2.3069	1.0758	3.3827

Number	Element	Mulliken
1	C	-0.265
2	C	-0.265
3	H	0.265
4	H	0.265

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>	15.782
(<r²>)^1/2	3.973

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)