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	hartrees
Energy at 0K	-77.188686
Energy at 298.15K	-77.188788
HF Energy	-76.848989
Nuclear repulsion energy	24.748244

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	3561	3381	0.00	62.23	0.25	0.40
2	Σ_g	1991	1890	0.00	50.51	0.16	0.28
3	Σ_u	3445	3270	95.83	0.00	0.00	0.00
4	Π_g	600	570	0.00	2.88	0.75	0.86
4	Π_g	600	570	0.00	2.88	0.75	0.86
5	Π_u	759	721	89.03	0.00	0.00	0.00
5	Π_u	759	721	89.03	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.604
C2	0.000	0.000	-0.604
H3	0.000	0.000	1.661
H4	0.000	0.000	-1.661

	C1	C2	H3	H4
C1		1.2074	1.0571	2.2646
C2	1.2074		2.2646	1.0571
H3	1.0571	2.2646		3.3217
H4	2.2646	1.0571	3.3217

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/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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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/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)