I was wondering.. it was taught to me that the Zeff increases down the group due to the penatraing power of of orbitals as the n=principal quantum number, value goes up. if that is the case, wont the number of shells added to the atom affect the Zeff? i mean as the no of shells increases, the distance increases too so even if it could penetrate to lets say 1 n lower eg, 4p to 3p, wont e-e repulsion take place?? can someone clear my doubts thanks a lot