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	hartrees
Energy at 0K	-77.309264
Energy at 298.15K	-77.309344
HF Energy	-77.309264
Nuclear repulsion energy	24.721305

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	3468	3421	0.00	58.84	0.23	0.38
2	Σ_g	2020	1992	0.00	81.10	0.13	0.24
3	Σ_u	3374	3328	74.73	0.00	0.00	0.00
4	Π_g	595	587	0.00	4.07	0.75	0.86
4	Π_g	595	587	0.00	4.07	0.75	0.86
5	Π_u	745	735	98.72	0.00	0.00	0.00
5	Π_u	745	735	98.72	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.669
H4	0.000	0.000	-1.669

	C1	C2	H3	H4
C1		1.2048	1.0664	2.2712
C2	1.2048		2.2712	1.0664
H3	1.0664	2.2712		3.3376
H4	2.2712	1.0664	3.3376

Number	Element	Mulliken
1	C	-0.165
2	C	-0.165
3	H	0.165
4	H	0.165

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B97D3/Def2TZVPP

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>	17.061
(<r²>)^1/2	4.130

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B97D3/Def2TZVPP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)