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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	-75.819328
Energy at 298.15K	-75.816302
HF Energy	-75.819328
Nuclear repulsion energy	15.167500

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.628
C2	0.000	0.000	-0.628

	C1	C2
C1		1.2560
C2	1.2560

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: PBEPBEultrafine/TZVP

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	-75.842589
Energy at 298.15K	-75.839560
HF Energy	-75.842589
Nuclear repulsion energy	14.505832

<r²>	11.717
(<r²>)^1/2	3.423

	C1	C2
C1		1.3133
C2	1.3133

<r²>	12.611
(<r²>)^1/2	3.551

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

using model chemistry: PBEPBEultrafine/TZVP

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^-)