Fluorine ground state electronic configuration

Deduce the ground-state electron configuration of the fluorine molecule and calculate its hond order. 

Which of these is the ground-state electron configuration for an atom of fluorine (atomic number = 9) ... 

Fluorine is a chemical element that in pure form occurs as a dimer of two fluorine atoms, F2. The fluorine atom has the ground state electron configuration ls22s22p5. There is only one stable, naturally occurring isotope of fluorine 19F. However, the radioactive isotopes 17F, 18F, and 20F are known. The inclusion of the isotope 18F (half-life 110 minutes) in bioor-ganic molecules is an important noninvasive technique used in the study of living tissue by positron emission tomography. 

Electrons for which the principal quantum number n is larger than the r ue of ii for the electron of interest contribute 0 to the r ue of S. Electrons with the same value of II as the electron of interest contribute 0.35 to the value of S. Electrons for which i is 1 less than ii for the electron of interest contribute 0.85, while those with even smaller values of n contribute 1.00. For example, consider fluorine, which has the ground-state electron configuration ls 2s 2p . For a valence electron in fluorine. Slater s rules tell us that S = (0.35 X 6) + (0.85 X 2) = 3.8. (Slater s rules ignore the contribution of an electron to itself in screening therefore, we consider only six ii = 2 electrons, not all seven). Thus, Zgjj = Z— S = 9 — 3.8 = 5.2+. 

There are 24 valence electrons iij BFs [7 from each fluorine (Zs lp ), 3 from the boron (2r 2fi)]. Placing these electrons in the most stable molecular orbitals, we obtain a ground-state configuration ... 

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