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State	Conformation	minimum conformation	conformer description	state description
1	1	yes	D*H	¹Σ_g⁺
3	1	yes	D*H	³Σ_g^-

	hartrees
Energy at 0K	-75.855232
Energy at 298.15K	-75.852205
HF Energy	-75.405764
Nuclear repulsion energy	15.331613

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.621
C2	0.000	0.000	-0.621

	C1	C2
C1		1.2422
C2	1.2422

	hartrees
Energy at 0K	-75.855232
Energy at 298.15K	-75.852205
HF Energy	-75.405764
Nuclear repulsion energy	15.331613

All results from a given calculation for C₂ (Carbon diatomic)

using model chemistry: CCSD(T)=FULL/cc-pVQZ

States and conformations

State 1 (¹Σ_g⁺)

State 2 (³Π_u)

State 3 (³Σ_g^-)

	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
You are here: Calculated > Energy > Optimized > Energy

	hartrees
Energy at 0K	-75.851199
Energy at 298.15K	-75.848169
HF Energy	-75.500732
Nuclear repulsion energy	14.524267

	C1	C2
C1		1.3112
C2	1.3112

All results from a given calculation for C2 (Carbon diatomic)

using model chemistry: CCSD(T)=FULL/cc-pVQZ

States and conformations

State 1 (1Σg+)

State 2 (3Πu)

State 3 (3Σg-)

All results from a given calculation for C₂ (Carbon diatomic)

State 1 (¹Σ_g⁺)

State 2 (³Π_u)

State 3 (³Σ_g^-)