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	hartrees
Energy at 0K	-76.797336
Energy at 298.15K	-76.797511
HF Energy	-76.731943
Nuclear repulsion energy	24.685547

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	3385	0.00	61.40	0.20	0.33
2	Σ_g	2044	1946	0.00	35.33	0.29	0.45
3	Σ_u	3452	3286	81.90	0.00	0.00	0.00
4	Π_g	660	628	0.00	1.98	0.75	0.86
4	Π_g	660	628	0.00	1.98	0.75	0.86
5	Π_u	778	741	101.74	0.00	0.00	0.00
5	Π_u	778	741	101.74	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		1.2098	1.0611	2.2710
C2	1.2098		2.2710	1.0611
H3	1.0611	2.2710		3.3321
H4	2.2710	1.0611	3.3321

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=FULL/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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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/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)