A catalyst precursor having the formula: AqMLn, wherein each A has the formula: M is a metal selected from the group consisting of group 3 to 13 elements and Lanthanide series elements; each L is a monovalent, bivalent, or trivalent anion; X and Y are each heteroatoms; cyclo is a cyclic moiety; each R1 is independently a group containing 1 to 50 atoms selected from the group consisting of hydrogen and group 13 to 17 elements, and two or more adjacent R1 groups may be joined to form a cyclic moiety; each R2 is independently a group containing 1 to 50 atoms selected from the group consisting of hydrogen and group 13 to 17 elements, and two or more adjacent R2 groups may be joined to form a cyclic moiety; Q is a bridging group; each m is independently an integer from 0 to 5; n is an integer from 1 to 4; q is 1 or 2; and when q is 2, the A groups are optionally connected by a bridging group Z is provided. The catalyst precursor may be made by reacting an organometal compound with a heteroatom-containing ligand. The catalyst precursor, when combined with an activating cocatalyst, is useful for the polymerization of olefins.