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State	Conformation	minimum conformation	conformer description	state description
1	1	yes	D*H	¹Σ_g⁺
2	1	yes	D*H	³Π_u
4	1	yes	D*H	¹Π_u

	hartrees
Energy at 0K	-75.839700
Energy at 298.15K	-75.836674
HF Energy	-75.839700
Nuclear repulsion energy

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.627
C2	0.000	0.000	-0.627

	C1	C2
C1		1.2542
C2	1.2542

Number	Element	Mulliken	CHELPG	AIM	ESP
1	C	0.000
2	C	0.000

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

using model chemistry: wB97X-D/6-31G*

States and conformations

State 1 (¹Σ_g⁺)

State 2 (³Π_u)

State 3 (³Σ_g^-)

State 4 (¹Π_u)

	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	-75.880417
Energy at 298.15K	-75.877389
HF Energy	-75.880417
Nuclear repulsion energy

<r²>	11.431
(<r²>)^1/2	3.381

	C1	C2
C1		1.3083
C2	1.3083

<r²>	12.262
(<r²>)^1/2	3.502

	C1	C2
C1		1.2462
C2	1.2462

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

using model chemistry: wB97X-D/6-31G*

States and conformations

State 1 (1Σg+)

State 2 (3Πu)

State 3 (3Σg-)

State 4 (1Πu)

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

State 1 (¹Σ_g⁺)

State 2 (³Π_u)

State 3 (³Σ_g^-)

State 4 (¹Π_u)