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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	-75.818784
Energy at 298.15K	-75.815758
HF Energy	-75.405784
Nuclear repulsion energy	15.379409

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.619
C2	0.000	0.000	-0.619

	C1	C2
C1		1.2387
C2	1.2387

	hartrees
Energy at 0K	-75.818784
Energy at 298.15K	-75.815758
HF Energy	-75.405784
Nuclear repulsion energy	15.379409

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

using model chemistry: CCSD=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	-75.831682
Energy at 298.15K	-75.828654
HF Energy	-75.501181
Nuclear repulsion energy	14.619661

	C1	C2
C1		1.3031
C2	1.3031

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

using model chemistry: CCSD=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^-)