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	hartrees
Energy at 0K	-77.221258
Energy at 298.15K	-77.221338
HF Energy	-77.221258
Nuclear repulsion energy	24.719649

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3562	3395	0.00	60.49	0.21	0.35
2	Σ_g	2103	2004	0.00	51.44	0.26	0.41
3	Σ_u	3459	3297	81.03	0.00	0.00	0.00
4	Π_g	577	550	0.00	1.72	0.75	0.86
4	Π_g	577	550	0.00	1.72	0.75	0.86
5	Π_u	781	745	88.80	0.00	0.00	0.00
5	Π_u	781	745	88.80	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.670
H4	0.000	0.000	-1.670

	C1	C2	H3	H4
C1		1.2044	1.0675	2.2719
C2	1.2044		2.2719	1.0675
H3	1.0675	2.2719		3.3393
H4	2.2719	1.0675	3.3393

Number	Element	Mulliken
1	C	-0.227
2	C	-0.227
3	H	0.227
4	H	0.227

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBE1PBE/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>	16.743
(<r²>)^1/2	4.092

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBE1PBE/6-31G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)