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	hartrees
Energy at 0K	-77.247555
Energy at 298.15K	-77.247661
HF Energy	-77.159464
Nuclear repulsion energy	24.506602

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	3540	3391	0.00	68.46	0.24	0.38
2	Σ_g	2028	1942	0.00	49.59	0.24	0.39
3	Σ_u	3447	3301	97.37	0.00	0.00	0.00
4	Π_g	601	576	0.00	1.33	0.75	0.86
4	Π_g	601	576	0.00	1.33	0.75	0.86
5	Π_u	765	733	77.25	0.00	0.00	0.00
5	Π_u	765	733	77.25	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.681
H4	0.000	0.000	-1.681

	C1	C2	H3	H4
C1		1.2171	1.0722	2.2893
C2	1.2171		2.2893	1.0722
H3	1.0722	2.2893		3.3615
H4	2.2893	1.0722	3.3615

Number	Element	Mulliken
1	C	-0.020
2	C	-0.020
3	H	0.020
4	H	0.020

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP/cc-pVDZ

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>	17.118
(<r²>)^1/2	4.137

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP/cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)