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	hartrees
Energy at 0K	-77.228093
Energy at 298.15K	-77.228007
HF Energy	-77.228093
Nuclear repulsion energy	24.426845

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	3455	3434	0.00	61.84	0.26	0.41
2	Σ_g	2005	1993	0.00	113.78	0.07	0.14
3	Σ_u	3353	3332	88.87	0.00	0.00	0.00
4	Π_g	498	495	0.00	3.11	0.75	0.86
4	Π_g	498	495	0.00	3.11	0.75	0.86
5	Π_u	697	693	97.75	0.00	0.00	0.00
5	Π_u	697	693	97.75	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	1.688
H4	0.000	0.000	-1.688

	C1	C2	H3	H4
C1		1.2198	1.0782	2.2981
C2	1.2198		2.2981	1.0782
H3	1.0782	2.2981		3.3763
H4	2.2981	1.0782	3.3763

Number	Element	Mulliken
1	C	0.372
2	C	0.372
3	H	-0.372
4	H	-0.372

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/aug-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>	17.409
(<r²>)^1/2	4.172

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)