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	hartrees
Energy at 0K	-12.413923
Energy at 298.15K	-12.414170
HF Energy	-12.413923
Nuclear repulsion energy	12.925202

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3525	3348	0.00
2	Σ_g	2019	1918	0.00
3	Σ_u	3410	3239	74.66
4	Π_g	708	672	0.00
4	Π_g	708	672	0.00
5	Π_u	804	764	139.10
5	Π_u	804	764	139.10

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.676
H4	0.000	0.000	-1.676

	C1	C2	H3	H4
C1		1.2187	1.0669	2.2857
C2	1.2187		2.2857	1.0669
H3	1.0669	2.2857		3.3526
H4	2.2857	1.0669	3.3526

Number	Element	Mulliken
1	C	-0.276
2	C	-0.276
3	H	0.276
4	H	0.276

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: mPW1PW91/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>	15.594
(<r²>)^1/2	3.949

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: mPW1PW91/CEP-121G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)