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	hartrees
Energy at 0K	-77.290713
Energy at 298.15K	-77.290759
Nuclear repulsion energy	24.703393

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3549	3395	0.00
2	Σ_g	2090	1999	0.00
3	Σ_u	3447	3298	76.00
4	Π_g	560	535	0.00
4	Π_g	560	535	0.00
5	Π_u	775	741	87.90
5	Π_u	775	741	87.90

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	1.670
H4	0.000	0.000	-1.670

	C1	C2	H3	H4
C1		1.2055	1.0675	2.2730
C2	1.2055		2.2730	1.0675
H3	1.0675	2.2730		3.3405
H4	2.2730	1.0675	3.3405

Number	Element	Mulliken	ESP
1	C	-0.222	-0.279
2	C	-0.222	-0.279
3	H	0.222	0.279
4	H	0.222	0.279

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/6-31G*

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>	16.739
(<r²>)^1/2	4.091

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/6-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)