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	hartrees
Energy at 0K	-77.260624
Energy at 298.15K	-77.260817
HF Energy	-77.260624
Nuclear repulsion energy	24.867068

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3524	3524	0.00
2	Σ_g	2079	2079	0.00
3	Σ_u	3422	3422	92.52
4	Π_g	678	678	0.00
4	Π_g	678	678	0.00
5	Π_u	772	772	98.63
5	Π_u	772	772	98.63

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.598
C2	0.000	0.000	-0.598
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.1960	1.0638	2.2598
C2	1.1960		2.2598	1.0638
H3	1.0638	2.2598		3.3237
H4	2.2598	1.0638	3.3237

Number	Element	Mulliken
1	C	-0.712
2	C	-0.712
3	H	0.712
4	H	0.712

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBE1PBE/aug-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>	16.955
(<r²>)^1/2	4.118

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBE1PBE/aug-cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)