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	hartrees
Energy at 0K	-77.232194
Energy at 298.15K	-77.232299
HF Energy	-77.232194
Nuclear repulsion energy	24.725096

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	3555	3392	0.00	62.35	0.20	0.34
2	Σ_g	2100	2004	0.00	52.47	0.25	0.41
3	Σ_u	3453	3295	89.67	0.00	0.00	0.00
4	Π_g	598	571	0.00	1.43	0.75	0.86
4	Π_g	598	571	0.00	1.43	0.75	0.86
5	Π_u	779	744	86.24	0.00	0.00	0.00
5	Π_u	779	744	86.24	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		1.2046	1.0663	2.2709
C2	1.2046		2.2709	1.0663
H3	1.0663	2.2709		3.3373
H4	2.2709	1.0663	3.3373

Number	Element	Mulliken
1	C	-0.186
2	C	-0.186
3	H	0.186
4	H	0.186

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HSEh1PBE/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>	16.736
(<r²>)^1/2	4.091

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HSEh1PBE/6-31G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)