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	hartrees
Energy at 0K	-75.691599
Energy at 298.15K	-75.688570
HF Energy	-75.463787
Nuclear repulsion energy	14.342067

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.664
C2	0.000	0.000	-0.664

	C1	C2
C1		1.3279
C2	1.3279

Number	Element	Mulliken	CHELPG	AIM	ESP
1	C	0.000
2	C	0.000

	x	y	z
x	0.000	0.000	0.000
y	0.000	0.000	0.000
z	0.000	0.000	0.000

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

using model chemistry: ROMP2/6-31G*

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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<r²>	12.634
(<r²>)^1/2	3.554

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

using model chemistry: ROMP2/6-31G*

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)