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	hartrees
Energy at 0K	-12.399604
Energy at 298.15K	-12.399827
HF Energy	-12.399604
Nuclear repulsion energy	12.904231

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	3493	3404	0.00	63.02	0.22	0.36
2	Σ_g	1995	1945	0.00	74.52	0.19	0.32
3	Σ_u	3382	3296	72.89	0.00	0.00	0.00
4	Π_g	686	668	0.00	7.50	0.75	0.86
4	Π_g	686	668	0.00	7.50	0.75	0.86
5	Π_u	798	778	141.15	0.00	0.00	0.00
5	Π_u	798	778	141.15	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.611
C2	0.000	0.000	-0.611
H3	0.000	0.000	1.678
H4	0.000	0.000	-1.678

	C1	C2	H3	H4
C1		1.2217	1.0672	2.2889
C2	1.2217		2.2889	1.0672
H3	1.0672	2.2889		3.3562
H4	2.2889	1.0672	3.3562

Number	Element	Mulliken
1	C	-0.288
2	C	-0.288
3	H	0.288
4	H	0.288

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3LYP/CEP-121G

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>	15.689
(<r²>)^1/2	3.961

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3LYP/CEP-121G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)