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	hartrees
Energy at 0K	-77.197067
Energy at 298.15K	-77.197193
HF Energy	-76.851359
Nuclear repulsion energy	24.715916

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	3546	3546	0.00	65.28	0.20	0.34
2	Σ_g	1982	1982	0.00	57.64	0.13	0.23
3	Σ_u	3452	3452	95.29	0.00	0.00	0.00
4	Π_g	620	620	0.00	3.54	0.75	0.86
4	Π_g	620	620	0.00	3.54	0.75	0.86
5	Π_u	769	769	94.74	0.00	0.00	0.00
5	Π_u	769	769	94.74	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	1.664
H4	0.000	0.000	-1.664

	C1	C2	H3	H4
C1		1.2087	1.0592	2.2679
C2	1.2087		2.2679	1.0592
H3	1.0592	2.2679		3.3271
H4	2.2679	1.0592	3.3271

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/Def2TZVPP

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/Def2TZVPP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)