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	hartrees
Energy at 0K	-77.198904
Energy at 298.15K	-77.198986
HF Energy	-77.133846
Nuclear repulsion energy	24.538489

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	3561	3561	0.00	70.09	0.20	0.33
2	Σ_g	2020	2020	0.00	41.05	0.27	0.42
3	Σ_u	3461	3461	77.85	0.00	0.00	0.00
4	Π_g	587	587	0.00	2.41	0.75	0.86
4	Π_g	587	587	0.00	2.41	0.75	0.86
5	Π_u	768	768	106.69	0.00	0.00	0.00
5	Π_u	768	768	106.69	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2185	1.0645	2.2831
C2	1.2185		2.2831	1.0645
H3	1.0645	2.2831		3.3476
H4	2.2831	1.0645	3.3476

Number	Element	Mulliken
1	C	-0.237
2	C	-0.237
3	H	0.237
4	H	0.237

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP/6-31G

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>	17.009
(<r²>)^1/2	4.124

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP/6-31G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)