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	hartrees
Energy at 0K	-76.851376
Energy at 298.15K	-76.851738
HF Energy	-76.851376
Nuclear repulsion energy	25.168599

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	3673	3344	0.00	37.50	0.39	0.56
2	Σ_g	2210	2012	0.00	144.04	0.05	0.09
3	Σ_u	3553	3235	95.59	0.00	0.00	0.00
4	Π_g	810	738	0.00	4.59	0.75	0.86
4	Π_g	810	738	0.00	4.59	0.75	0.86
5	Π_u	870	792	113.01	0.00	0.00	0.00
5	Π_u	870	792	113.01	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.590
C2	0.000	0.000	-0.590
H3	0.000	0.000	1.644
H4	0.000	0.000	-1.644

	C1	C2	H3	H4
C1		1.1803	1.0540	2.2343
C2	1.1803		2.2343	1.0540
H3	1.0540	2.2343		3.2882
H4	2.2343	1.0540	3.2882

Number	Element	Mulliken
1	C	-0.657
2	C	-0.657
3	H	0.657
4	H	0.657

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HF/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>	16.783
(<r²>)^1/2	4.097

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HF/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)