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	hartrees
Energy at 0K	-77.203439
Energy at 298.15K	-77.203498
HF Energy	-77.203439
Nuclear repulsion energy	24.446694

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3487	3439	0.00
2	Σ_g	2015	1987	0.00
3	Σ_u	3381	3335	75.27
4	Π_g	576	568	0.00
4	Π_g	576	568	0.00
5	Π_u	755	745	103.99
5	Π_u	755	745	103.99

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.610
C2	0.000	0.000	-0.610
H3	0.000	0.000	1.683
H4	0.000	0.000	-1.683

	C1	C2	H3	H4
C1		1.2210	1.0729	2.2939
C2	1.2210		2.2939	1.0729
H3	1.0729	2.2939		3.3668
H4	2.2939	1.0729	3.3668

Number	Element	Mulliken
1	C	-0.217
2	C	-0.217
3	H	0.217
4	H	0.217

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/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>	17.012
(<r²>)^1/2	4.125

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/6-31G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)