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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	-75.375113
Energy at 298.15K	-75.372086
HF Energy	-75.375113
Nuclear repulsion energy	15.049772

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.633
C2	0.000	0.000	-0.633

	C1	C2
C1		1.2658
C2	1.2658

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: PBEPBE/3-21G

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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You are here: Calculated > Energy > Optimized > Energy

	hartrees
Energy at 0K	-75.392842
Energy at 298.15K	-75.389811
HF Energy	-75.392842
Nuclear repulsion energy	14.274093

<r²>	11.684
(<r²>)^1/2	3.418

	C1	C2
C1		1.3346
C2	1.3346

<r²>	12.663
(<r²>)^1/2	3.559

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

using model chemistry: PBEPBE/3-21G

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)