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	hartrees
Energy at 0K	-12.503448
Energy at 298.15K	-12.503541
HF Energy	-12.503448
Nuclear repulsion energy	12.758108

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3398	3398	0.00
2	Σ_g	1943	1943	0.00
3	Σ_u	3285	3285	87.90
4	Π_g	597	597	0.00
4	Π_g	597	597	0.00
5	Π_u	747	747	140.62
5	Π_u	747	747	140.62

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.617
C2	0.000	0.000	-0.617
H3	0.000	0.000	1.699
H4	0.000	0.000	-1.699

	C1	C2	H3	H4
C1		1.2334	1.0827	2.3161
C2	1.2334		2.3161	1.0827
H3	1.0827	2.3161		3.3988
H4	2.3161	1.0827	3.3988

Number	Element	Mulliken
1	C	-0.287
2	C	-0.287
3	H	0.287
4	H	0.287

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: LSDA/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>	15.928
(<r²>)^1/2	3.991

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: LSDA/CEP-121G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)