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	hartrees
Energy at 0K	-77.301837
Energy at 298.15K	-77.301993
HF Energy	-77.185671
Nuclear repulsion energy	24.809926

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	3527	3527	0.00	57.48	0.25	0.40
2	Σ_g	2025	2025	0.00	96.50	0.07	0.14
3	Σ_u	3433	3433	92.26	0.00	0.00	0.00
4	Π_g	647	647	0.00	3.62	0.75	0.86
4	Π_g	647	647	0.00	3.62	0.75	0.86
5	Π_u	764	764	97.20	0.00	0.00	0.00
5	Π_u	764	764	97.20	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.601
C2	0.000	0.000	-0.601
H3	0.000	0.000	1.661
H4	0.000	0.000	-1.661

	C1	C2	H3	H4
C1		1.2013	1.0608	2.2622
C2	1.2013		2.2622	1.0608
H3	1.0608	2.2622		3.3230
H4	2.2622	1.0608	3.3230

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=FULL/6-311+G(3df,2p)

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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HF vs MP2 Bad vib. Calc. vs exp. 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Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP=FULL/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)