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	hartrees
Energy at 0K	-77.248614
Energy at 298.15K	-77.248701
HF Energy	-77.248614
Nuclear repulsion energy	24.659254

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	3439	3439	0.00	57.52	0.27	0.42
2	Σ_g	2007	2007	0.00	106.32	0.07	0.14
3	Σ_u	3342	3342	85.41	0.00	0.00	0.00
4	Π_g	605	605	0.00	3.58	0.75	0.86
4	Π_g	605	605	0.00	3.58	0.75	0.86
5	Π_u	734	734	97.88	0.00	0.00	0.00
5	Π_u	734	734	97.88	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	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2071	1.0706	2.2777
C2	1.2071		2.2777	1.0706
H3	1.0706	2.2777		3.3484
H4	2.2777	1.0706	3.3484

Number	Element	Mulliken
1	C	-0.208
2	C	-0.208
3	H	0.208
4	H	0.208

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/6-311+G(3df,2p)

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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HF vs MP2 Bad vib. Calc. vs exp. 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<r²>	17.197
(<r²>)^1/2	4.147

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)