A metal complex of a polyvalent aryloxyether corresponding to the formula: where M 3 is Hf or Zr, preferably Zr; Ar 4 corresponds to the formula: wherein R 11 independently in each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen, or two R 11 groups together are part of a ring attached to the aryl group in two positions, with the proviso that in at least one occurrence R 11 or the divalent derivative of two such R 11 groups, is independently selected from the group consisting of tertiary alkyl-, cycloalkyl-, trihydrocarbylsilyl-, tri(hydrocarbyl)silylhydrocarbyl- and tri(hydrocarbyl)phenyl- groups having from 3 to 20 nonhydrogen atoms or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen and/or lacks co-planarity with the aryl group to which it is attached; T 4 independently each occurrence is a C 2-20 alkylene, cycloalkylene or cycloalkenylene group, or an inertly substituted derivative thereof; R 21 independently each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or di(hydrocarbyl)amino group of up to 50 atoms not counting hydrogen; R 3 independently in each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or amino of up to 50 atoms not counting hydrogen, or two R 3 groups on the same arylene ring together or an R 3 and an R 21 group on the same or different arylene ring together form a divalent ligand group attached to the arylene group in two positions or join two different arylene rings together, with the proviso that at least two R 3 groups located on different arylenoxy groups are independently selected from the group consisting of tertiary alkyl-, cycloalkyl-, trihydrocarbylsilyl-, tri(hydrocarbyl)silylhydrocarbyl- and tri(hydrocarbyl)phenyl- groups having from 3 to 20 nonhydrogen atoms or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen or at least one R 3 group is a linear alkyl group; and R D, independently each occurrence is halo or a hydrocarbyl or trihydrocarbylsilyl group of up to 20 atoms not counting hydrogen, or 2 R D groups together are a hydrocarbylene, hydrocarbadiyl, diene, or poly(hydrocarbyl)silylene group. where M 3 is Hf or Zr, preferably Zr; Ar 4 corresponds to the formula: wherein R 11 independently in each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen, or two R 11 groups together are part of a ring attached to the aryl group in two positions, with the proviso that in at least one occurrence R 11 or the divalent derivative of two such R 11 groups, is independently selected from the group consisting of tertiary alkyl-, cycloalkyl-, trihydrocarbylsilyl-, tri(hydrocarbyl)silylhydrocarbyl- and tri(hydrocarbyl)phenyl- groups having from 3 to 20 nonhydrogen atoms or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen and/or lacks co-planarity with the aryl group to which it is attached; T 4 independently each occurrence is a C 2-20 alkylene, cycloalkylene or cycloalkenylene group, or an inertly substituted derivative thereof; R 21 independently each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or di(hydrocarbyl)amino group of up to 50 atoms not counting hydrogen; R 3 independently in each occurrence is hydrogen, halo, hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, alkoxy or amino of up to 50 atoms not counting hydrogen, or two R 3 groups on the same arylene ring together or an R 3 and an R 21 group on the same or different arylene ring together form a divalent ligand group attached to the arylene group in two positions or join two different arylene rings together, with the proviso that at least two R 3 groups located on different arylenoxy groups are independently selected from the group consisting of tertiary alkyl-, cycloalkyl-, trihydrocarbylsilyl-, tri(hydrocarbyl)silylhydrocarbyl- and tri(hydrocarbyl)phenyl- groups having from 3 to 20 nonhydrogen atoms or di(hydrocarbyl)amino of up to 50 atoms not counting hydrogen or at least one R 3 group is a linear alkyl group; and R D, independently each occurrence is halo or a hydrocarbyl or trihydrocarbylsilyl group of up to 20 atoms not counting hydrogen, or 2 R D groups together are a hydrocarbylene, hydrocarbadiyl, diene, or poly(hydrocarbyl)silylene group.