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	hartrees
Energy at 0K	-76.796384
Energy at 298.15K	-76.796555
HF Energy	-76.731940
Nuclear repulsion energy	24.684757

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	3556	3556	0.00	61.41	0.20	0.33
2	Σ_g	2044	2044	0.00	35.33	0.29	0.46
3	Σ_u	3452	3452	81.89	0.00	0.00	0.00
4	Π_g	660	660	0.00	1.99	0.75	0.86
4	Π_g	660	660	0.00	1.99	0.75	0.86
5	Π_u	778	778	101.76	0.00	0.00	0.00
5	Π_u	778	778	101.76	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.605
C2	0.000	0.000	-0.605
H3	0.000	0.000	1.666
H4	0.000	0.000	-1.666

	C1	C2	H3	H4
C1		1.2099	1.0611	2.2710
C2	1.2099		2.2710	1.0611
H3	1.0611	2.2710		3.3322
H4	2.2710	1.0611	3.3322

Number	Element	Mulliken
1	C	-0.262
2	C	-0.262
3	H	0.262
4	H	0.262

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP/3-21G*

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>	16.960
(<r²>)^1/2	4.118

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP/3-21G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)