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	hartrees
Energy at 0K	-76.590890
Energy at 298.15K	-76.590909
HF Energy	-76.393846
Nuclear repulsion energy	24.564620

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3493	3341	0.00
2	Σ_g	2034	1945	0.00
3	Σ_u	3387	3240	59.51
4	Π_g	555	530	0.00
4	Π_g	555	530	0.00
5	Π_u	740	708	95.51
5	Π_u	740	708	95.51

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.607
C2	0.000	0.000	-0.607
H3	0.000	0.000	1.675
H4	0.000	0.000	-1.675

	C1	C2	H3	H4
C1		1.2150	1.0680	2.2830
C2	1.2150		2.2830	1.0680
H3	1.0680	2.2830		3.3510
H4	2.2830	1.0680	3.3510

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCD/3-21G*

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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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: CCD/3-21G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)