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	hartrees
Energy at 0K	-76.792762
Energy at 298.15K	-76.793178
HF Energy	-76.792762
Nuclear repulsion energy	24.970279

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	3734	3372	0.00	56.44	0.18	0.31
2	Σ_g	2209	1995	0.00	59.45	0.27	0.42
3	Σ_u	3616	3264	98.41	0.00	0.00	0.00
4	Π_g	899	811	0.00	6.22	0.75	0.86
4	Π_g	899	811	0.00	6.22	0.75	0.86
5	Π_u	892	805	141.10	0.00	0.00	0.00
5	Π_u	892	805	141.10	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.597
C2	0.000	0.000	-0.597
H3	0.000	0.000	1.650
H4	0.000	0.000	-1.650

	C1	C2	H3	H4
C1		1.1942	1.0529	2.2470
C2	1.1942		2.2470	1.0529
H3	1.0529	2.2470		3.2999
H4	2.2470	1.0529	3.2999

Number	Element	Mulliken
1	C	-0.320
2	C	-0.320
3	H	0.320
4	H	0.320

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HF/6-31G

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>	16.753
(<r²>)^1/2	4.093

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HF/6-31G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)