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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

	hartrees
Energy at 0K	-75.703266
Energy at 298.15K	-75.700240
HF Energy	-75.386656
Nuclear repulsion energy	14.940081

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.638
C2	0.000	0.000	-0.638

	C1	C2
C1		1.2751
C2	1.2751

	hartrees
Energy at 0K	-75.695230
Energy at 298.15K	-75.692201
HF Energy	-75.480298
Nuclear repulsion energy	14.281209

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

using model chemistry: MP2/cc-pCVDZ

States and conformations

State 1 (¹Σ_g⁺)

State 2 (³Π_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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	C1	C2
C1		1.3339
C2	1.3339

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

using model chemistry: MP2/cc-pCVDZ

States and conformations

State 1 (1Σg+)

State 2 (3Πu)

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

State 1 (¹Σ_g⁺)

State 2 (³Π_u)