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	hartrees
Energy at 0K	-77.228312
Energy at 298.15K	-77.228383
HF Energy	-77.228312
Nuclear repulsion energy	24.725686

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	3562	3387	0.00	61.05	0.21	0.35
2	Σ_g	2102	1999	0.00	51.41	0.26	0.41
3	Σ_u	3459	3289	79.32	0.00	0.00	0.00
4	Π_g	574	546	0.00	1.66	0.75	0.86
4	Π_g	574	546	0.00	1.66	0.75	0.86
5	Π_u	782	743	87.85	0.00	0.00	0.00
5	Π_u	782	743	87.85	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		1.2041	1.0672	2.2713
C2	1.2041		2.2713	1.0672
H3	1.0672	2.2713		3.3385
H4	2.2713	1.0672	3.3385

Number	Element	Mulliken
1	C	-0.224
2	C	-0.224
3	H	0.224
4	H	0.224

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>	16.737
(<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)