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	hartrees
Energy at 0K	-76.593310
Energy at 298.15K	-76.593313
HF Energy	-76.393594
Nuclear repulsion energy	24.534865

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3481	3283	0.00
2	Σ_g	2019	1904	0.00
3	Σ_u	3376	3184	61.19
4	Π_g	541	510	0.00
4	Π_g	541	510	0.00
5	Π_u	736	694	94.18
5	Π_u	736	694	94.18

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.608
C2	0.000	0.000	-0.608
H3	0.000	0.000	1.677
H4	0.000	0.000	-1.677

	C1	C2	H3	H4
C1		1.2168	1.0685	2.2854
C2	1.2168		2.2854	1.0685
H3	1.0685	2.2854		3.3539
H4	2.2854	1.0685	3.3539

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD/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: CCSD/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)