Fig. presents the relative energetics of the ortho-and meta-substituted intermediate E ortho 0 (R) -E meta 0 (R) when the cavity polarization ê = (θ 1 , ϕ 1 ) (see Fig. ) as a function of cavity frequency ω c and the cavity mode volume V (in units of nm 3 ). Fig. presents the relative energetics of the para-and meta-substituted intermediate E para 0 (R) -E meta 0 (R) when ê = (θ 2 , ϕ 2 ) (see Fig. ). Here, we focus on the range of frequency ω c ≈ 1 -4 eV which is within the typical range possible of nano-cavity designs. The cavity frequency of the NPoM cavity depends on the materials of the nanoparticle, the size of the nanoparticle, and the gap size between the particle and the mirror surface. The typical value is for gold nano-particle about ω c ≈ 2 eV (600 nm), silver nano-particle about ω c ≈ 2.5 eV (500 nm) and aluminum nano-particle about ω c ≈ 3 eV (400 nm). In particular, for the recent experiments on a single emitter strongly coupled to the plasmonic nano-cavity, with gold nano-particle the cavity has a frequency of ω c = 1.8 eV. Assuming mode volumes eqivalent to those previously reported ( V = 0.15 nm 3 ), the equivalent coupling strength is A 0 = 0.3 a.u. (or λ = 0.1 a.u.) and field intensity is E = 10.9 V/nm. With these parameters, one can lower the energy of ortho-complex by 6.74 kcal/mol compared to the meta-substituted intermediate and lower the energy of para-substituted intermediate by 2.24 kcal/mol compared to the meta-substituted intermediate. Although coupling to the cavity does not dramatically lower the energy of the ortho/para-substituted intermediates, these computed coupling strengths indicate favorability for the ortho or para products, and thus one should expect to obtain the mixtures of these products together with the meta-substituted product. Fig. presents the relative stability of the three positively charged intermediate species when cavity (a) polarized along the ê = (θ 1 , ϕ 1 ) direction (primary axis of the molecule) or (b) polarized along the ê = (θ 2 , ϕ 2 ) direction. The relative energy difference is reported as (a) the polaritonic ground states between the ortho-PhNO 2 -Br + and the meta-PhNO 2 -Br + cationic intermediate species, denoted as