To explore the influence of collective effects and molecular interactions on the reaction dynamics, we extend our investigation to include two molecules inside the cavity mode. These two molecules can interact indirectly by simultaneously coupling to the same cavity mode or directly by inter-molecular dipole-dipole interaction, denoted as ∆ 12 = ∆ (see Eq. ( )). We begin by examining a homodimer, where both molecules are identical, and subsequently, a heterodimer with different masses. Additionally, we account for the dipole orientation effect in two configurations: parallel and anti-parallel. In the parallel configuration, the dipoles of both molecules align in the same direction as the light polarization ⃗ e. In the antiparallel configuration, one molecular dipole aligns with the light polarization, i.e. ⃗ µ 1 (x 1 ) ⋅ ⃗ e = x 1 , while the other points in the opposite direction, ⃗ µ 2 (x 2 ) ⋅ ⃗ e = -x 2 , as illustrated in Fig. ).