$(I)\, Pt(SCN)_2 - 3PEt_3,$ $(II)\,CoBr ·SO_4 · 5NH_3$ $(III)\, FeCl_2 · 6H_2O$
$(II) \,[CoBr(NH_3)_5]SO_4:$ Exhibit only ionization isomerism.
$(III)\, [Fe(H_2O)_6]Cl_2:$ Exhibits only hydrate isomerism.
$($At. No. $Mo = 42, Pt = 78)$
(Atomic nos. $Mn = 25,\,Fe = 26,\,Co = 27$)