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	hartrees
Energy at 0K	-12.211720
Energy at 298.15K	-12.211572
HF Energy	-12.029264
Nuclear repulsion energy	12.838986

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3467	3196	0.00
2	Σ_g	1977	1823	0.00
3	Σ_u	3359	3097	51.08
4	Π_g	429	395	0.00
4	Π_g	429	395	0.00
5	Π_u	759	700	123.67
5	Π_u	759	700	123.67

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.614
C2	0.000	0.000	-0.614
H3	0.000	0.000	1.686
H4	0.000	0.000	-1.686

	C1	C2	H3	H4
C1		1.2289	1.0713	2.3002
C2	1.2289		2.3002	1.0713
H3	1.0713	2.3002		3.3714
H4	2.3002	1.0713	3.3714

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CISD/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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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: CISD/CEP-121G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)