On the Solid Solubility and Structural Properties of PdAs(2-x)Sb(x), PtP(2-x)As(x), PtP(2-x)Sb(x), PtP(2-x)Bi(x), PtAs(2-x)Sb(x), PtAs(2-x)Bi(x), PtSb(2-x)Bi(x), Pd(1-m)Pt(m)As2, Pd(1-m)Pt(m)Sb2, Pd(1-m)Au(m)Sb2, and Pt(1-m)Au(m)Sb2.