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	hartrees
Energy at 0K	-77.218452
Energy at 298.15K	-77.218373
HF Energy	-77.218452
Nuclear repulsion energy	24.511995

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	3468	3421	0.00	68.43	0.21	0.34
2	Σ_g	2025	1998	0.00	50.03	0.26	0.41
3	Σ_u	3371	3325	82.48	0.00	0.00	0.00
4	Π_g	487	481	0.00	0.80	0.75	0.86
4	Π_g	487	481	0.00	0.80	0.75	0.86
5	Π_u	740	730	79.51	0.00	0.00	0.00
5	Π_u	740	730	79.51	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.608
C2	0.000	0.000	-0.608
H3	0.000	0.000	1.681
H4	0.000	0.000	-1.681

	C1	C2	H3	H4
C1		1.2161	1.0733	2.2895
C2	1.2161		2.2895	1.0733
H3	1.0733	2.2895		3.3628
H4	2.2895	1.0733	3.3628

Number	Element	Mulliken
1	C	-0.154
2	C	-0.154
3	H	0.154
4	H	0.154

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>	16.918
(<r²>)^1/2	4.113

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)