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	hartrees
Energy at 0K	-77.256011
Energy at 298.15K	-77.256079
HF Energy	-77.256011
Nuclear repulsion energy	24.673370

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3439	3439	0.00
2	Σ_g	2009	2009	0.00
3	Σ_u	3344	3344	83.73
4	Π_g	590	590	0.00
4	Π_g	590	590	0.00
5	Π_u	735	735	93.18
5	Π_u	735	735	93.18

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.603
C2	0.000	0.000	-0.603
H3	0.000	0.000	1.673
H4	0.000	0.000	-1.673

	C1	C2	H3	H4
C1		1.2064	1.0701	2.2764
C2	1.2064		2.2764	1.0701
H3	1.0701	2.2764		3.3465
H4	2.2764	1.0701	3.3465

Number	Element	Mulliken
1	C	-0.158
2	C	-0.158
3	H	0.158
4	H	0.158

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBE/cc-pVQZ

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>	17.120
(<r²>)^1/2	4.138

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBE/cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)