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	hartrees
Energy at 0K	-12.422836
Energy at 298.15K	-12.423009
HF Energy	-12.422836
Nuclear repulsion energy	12.998427

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3513	3513	0.00	69.33	0.26	0.41
2	Σ_g	2058	2058	0.00	87.67	0.20	0.33
3	Σ_u	3411	3411	56.26	0.00	0.00	0.00
4	Π_g	649	649	0.00	7.61	0.75	0.86
4	Π_g	649	649	0.00	7.61	0.75	0.86
5	Π_u	795	795	120.86	0.00	0.00	0.00
5	Π_u	795	795	120.86	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.603
C2	0.000	0.000	-0.603
H3	0.000	0.000	1.672
H4	0.000	0.000	-1.672

	C1	C2	H3	H4
C1		1.2060	1.0693	2.2753
C2	1.2060		2.2753	1.0693
H3	1.0693	2.2753		3.3446
H4	2.2753	1.0693	3.3446

Number	Element	Mulliken
1	C	-0.322
2	C	-0.322
3	H	0.322
4	H	0.322

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: wB97X-D/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>	15.437
(<r²>)^1/2	3.929

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: wB97X-D/CEP-121G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)