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	hartrees
Energy at 0K	-12.398617
Energy at 298.15K	-12.398743
HF Energy	-12.398617
Nuclear repulsion energy	12.732160

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	3518	3398	0.00	51.84	0.44	0.61
2	Σ_g	2061	1991	0.00	64.74	0.28	0.44
3	Σ_u	3396	3279	100.30	0.00	0.00	0.00
4	Π_g	599	578	0.00	23.46	0.75	0.86
4	Π_g	599	578	0.00	23.46	0.75	0.86
5	Π_u	819	790	136.41	0.00	0.00	0.00
5	Π_u	819	790	136.41	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.621
C2	0.000	0.000	-0.621
H3	0.000	0.000	1.697
H4	0.000	0.000	-1.697

	C1	C2	H3	H4
C1		1.2427	1.0753	2.3181
C2	1.2427		2.3181	1.0753
H3	1.0753	2.3181		3.3934
H4	2.3181	1.0753	3.3934

Number	Element	Mulliken
1	C	-0.376
2	C	-0.376
3	H	0.376
4	H	0.376

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3LYP/CEP-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>	15.826
(<r²>)^1/2	3.978

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3LYP/CEP-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)