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	hartrees
Energy at 0K	-77.148394
Energy at 298.15K	-77.148475
HF Energy	-76.838932
Nuclear repulsion energy	24.602419

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	3374	0.00	64.28	0.26	0.41
2	Σ_g	1974	1872	0.00	39.10	0.21	0.35
3	Σ_u	3466	3288	92.89	0.00	0.00	0.00
4	Π_g	576	547	0.00	2.89	0.75	0.86
4	Π_g	576	547	0.00	2.89	0.75	0.86
5	Π_u	773	734	89.37	0.00	0.00	0.00
5	Π_u	773	734	89.37	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.607
C2	0.000	0.000	-0.607
H3	0.000	0.000	1.671
H4	0.000	0.000	-1.671

	C1	C2	H3	H4
C1		1.2142	1.0641	2.2783
C2	1.2142		2.2783	1.0641
H3	1.0641	2.2783		3.3425
H4	2.2783	1.0641	3.3425

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/6-311G**

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: MP2=FULL/6-311G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)