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	hartrees
Energy at 0K	-77.251247
Energy at 298.15K	-77.251344
HF Energy	-77.251247
Nuclear repulsion energy	24.660060

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	3443	3404	0.00	57.72	0.27	0.43
2	Σ_g	2009	1986	0.00	116.44	0.06	0.12
3	Σ_u	3342	3304	84.85	0.00	0.00	0.00
4	Π_g	609	602	0.00	2.82	0.75	0.86
4	Π_g	609	602	0.00	2.82	0.75	0.86
5	Π_u	738	729	95.73	0.00	0.00	0.00
5	Π_u	738	729	95.73	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		1.2072	1.0703	2.2775
C2	1.2072		2.2775	1.0703
H3	1.0703	2.2775		3.3477
H4	2.2775	1.0703	3.3477

Number	Element	Mulliken
1	C	-0.547
2	C	-0.547
3	H	0.547
4	H	0.547

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/aug-cc-pVTZ

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>	17.200
(<r²>)^1/2	4.147

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)