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	hartrees
Energy at 0K	-77.271683
Energy at 298.15K	-77.271652
HF Energy	-77.172028
Nuclear repulsion energy	24.739538

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	3531	3531	0.00	58.50	0.28	0.43
2	Σ_g	2024	2024	0.00	51.10	0.22	0.36
3	Σ_u	3436	3436	73.93	0.00	0.00	0.00
4	Π_g	511	511	0.00	3.92	0.75	0.86
4	Π_g	511	511	0.00	3.92	0.75	0.86
5	Π_u	751	751	100.64	0.00	0.00	0.00
5	Π_u	751	751	100.64	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.603
C2	0.000	0.000	-0.603
H3	0.000	0.000	1.666
H4	0.000	0.000	-1.666

	C1	C2	H3	H4
C1		1.2050	1.0633	2.2683
C2	1.2050		2.2683	1.0633
H3	1.0633	2.2683		3.3316
H4	2.2683	1.0633	3.3316

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=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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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/6-311G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)