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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	-75.253177
Energy at 298.15K	-75.250150
HF Energy	-74.953228
Nuclear repulsion energy	14.814436

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.643
C2	0.000	0.000	-0.643

	C1	C2
C1		1.2855
C2	1.2855

	hartrees
Energy at 0K	-75.253177
Energy at 298.15K	-75.250150
HF Energy	-74.953228
Nuclear repulsion energy	14.814436

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

using model chemistry: MP4=FULL/3-21G

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	-75.225061
Energy at 298.15K	-75.222028
HF Energy	-75.039164
Nuclear repulsion energy	14.130827

	C1	C2
C1		1.3477
C2	1.3477

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

using model chemistry: MP4=FULL/3-21G

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^-)