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	hartrees
Energy at 0K	-77.325973
Energy at 298.15K	-77.326144
HF Energy	-77.325973
Nuclear repulsion energy	24.854477

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	3518	3518	0.00	51.32	0.29	0.44
2	Σ_g	2071	2071	0.00	120.19	0.05	0.10
3	Σ_u	3413	3413	89.58	0.00	0.00	0.00
4	Π_g	664	664	0.00	2.85	0.75	0.86
4	Π_g	664	664	0.00	2.85	0.75	0.86
5	Π_u	768	768	97.64	0.00	0.00	0.00
5	Π_u	768	768	97.64	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.599
C2	0.000	0.000	-0.599
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.1970	1.0635	2.2605
C2	1.1970		2.2605	1.0635
H3	1.0635	2.2605		3.3240
H4	2.2605	1.0635	3.3240

Number	Element	Mulliken
1	C	-0.952
2	C	-0.952
3	H	0.952
4	H	0.952

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/daug-cc-pVTZ

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>	16.943
(<r²>)^1/2	4.116

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/daug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)