Pb and Cl
Pb and Zn
Zn and Cl
Fe and Mg
Fe and F
Mg and F
Ag and O
Ag and Ni
Na and Br
Br and I
Na and I
K and H
K and O
H and O
Co and Cl
Cl and Cs
Co and Cs
Cr and Ni
Cr and F
F and Ni
Ca and I
Ca and Br
D