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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	-75.732535
Energy at 298.15K	-75.729508
HF Energy	-75.386444
Nuclear repulsion energy	14.965437

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.636
C2	0.000	0.000	-0.636

	C1	C2
C1		1.2726
C2	1.2726

	hartrees
Energy at 0K	-75.732535
Energy at 298.15K	-75.729508
HF Energy	-75.386444
Nuclear repulsion energy	14.965437

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

using model chemistry: QCISD(T)=FULL/cc-pVDZ

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	-75.729184
Energy at 298.15K	-75.726154
HF Energy	-75.479358
Nuclear repulsion energy	14.207097

	C1	C2
C1		1.3405
C2	1.3405

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

using model chemistry: QCISD(T)=FULL/cc-pVDZ

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^-)