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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	-75.772733
Energy at 298.15K	-75.769707
HF Energy	-75.401449
Nuclear repulsion energy	15.339102

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

	C1	C2
C1		1.2419
C2	1.2419

	hartrees
Energy at 0K	-75.772733
Energy at 298.15K	-75.769707
HF Energy	-75.401449
Nuclear repulsion energy	15.339102

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

using model chemistry: CCSD=FULL/cc-pVTZ

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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You are here: Calculated > Energy > Optimized > Energy

	hartrees
Energy at 0K	-75.785316
Energy at 298.15K	-75.782288
HF Energy	-75.496649
Nuclear repulsion energy	14.586613

	C1	C2
C1		1.3060
C2	1.3060

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

using model chemistry: CCSD=FULL/cc-pVTZ

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^-)