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	hartrees
Energy at 0K	-77.331453
Energy at 298.15K	-77.331504
HF Energy	-77.331453
Nuclear repulsion energy	24.685441

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	3539	3393	0.00	69.25	0.21	0.35
2	Σ_g	2072	1987	0.00	52.59	0.26	0.41
3	Σ_u	3440	3298	77.55	0.00	0.00	0.00
4	Π_g	555	532	0.00	1.45	0.75	0.86
4	Π_g	555	532	0.00	1.45	0.75	0.86
5	Π_u	780	748	85.09	0.00	0.00	0.00
5	Π_u	780	748	85.09	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.604
C2	0.000	0.000	-0.604
H3	0.000	0.000	1.669
H4	0.000	0.000	-1.669

	C1	C2	H3	H4
C1		1.2077	1.0656	2.2733
C2	1.2077		2.2733	1.0656
H3	1.0656	2.2733		3.3389
H4	2.2733	1.0656	3.3389

Number	Element	Mulliken
1	C	-0.184
2	C	-0.184
3	H	0.184
4	H	0.184

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: TPSSh/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>	16.758
(<r²>)^1/2	4.094

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: TPSSh/6-31G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)