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	hartrees
Energy at 0K	-77.228526
Energy at 298.15K	-77.228441
HF Energy	-77.228526
Nuclear repulsion energy	24.433186

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	3450	3450	0.00	61.89	0.28	0.43
2	Σ_g	2004	2004	0.00	124.89	0.06	0.10
3	Σ_u	3344	3344	89.81	0.00	0.00	0.00
4	Π_g	496	496	0.00	2.40	0.75	0.86
4	Π_g	496	496	0.00	2.40	0.75	0.86
5	Π_u	700	700	95.77	0.00	0.00	0.00
5	Π_u	700	700	95.77	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.610
C2	0.000	0.000	-0.610
H3	0.000	0.000	1.687
H4	0.000	0.000	-1.687

	C1	C2	H3	H4
C1		1.2198	1.0773	2.2971
C2	1.2198		2.2971	1.0773
H3	1.0773	2.2971		3.3744
H4	2.2971	1.0773	3.3744

Number	Element	Mulliken
1	C	0.294
2	C	0.294
3	H	-0.294
4	H	-0.294

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/daug-cc-pVDZ

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>	17.406
(<r²>)^1/2	4.172

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/daug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)