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Nine compounds based on o-carboxylphenoxyacetateacid (H2OCPA) ligand: [Cu(OCPA)(4,4′-bipy)0.5]n(1), {[Cu2(OCPA)2(4,4′-bipy)2(H2O)]·H2O}n(2), [Co2(OCPA)2(4,4′-bipy)(H2O)4] (3), {[Co(OCPA)(4,4′-bipy)0.5(H2O)]·H2O}n(4), {[Co(OCPA)(4,4′-bipy)1.5]·0.5H2O}n(5), [Ni2(OCPA)2(4,4′-bipy)(H2O)4] (6), {[Ni(OCPA)(4,4′-bipy)1.5]·2H2O}n(7), {[Zn(OCPA)(4,4′-bipy)0.5(H2O)]·H2O}n(8), and [Mn(OCPA)(H2O)]n(9) (4,4′-bipy = 4,4′-bipyridine)were synthesized by hydrothermal methods. The results of structuralanalyses reveal that the giant structural divergence of the compoundswith same metal ions mainly originated from the different amountsof 4,4′-bipy used in syntheses. For Cu-containing compounds,the structural divergences are from one-dimensional (1D) chain 1to two-dimensional (2D) network 2; for Co,through binuclear 3to 1D ladder-like 4,and to another different 1D ladder-like chain 5; forNi, from binuclear 6to 1D chain 7. Butfor Zn and Mn, 1D chain 8and 2D network 9are obtained with the presence of excess 4,4′-bipy. Compound 9crystallizes in chiral space group P21with a second harmonic generation (SHG) efficiency of 0.8times that of urea. The magnetic studies show that compounds 1and 9have antiferromagnetic coupling betweenthe adjacent metallic ions. Compound 4is a weak ferromagnetbased on antiferromagnetic interaction and spin canting. Both thebifurcation temperature of the field-cooled (FC) and zero-field-cooled(ZFC) and the peaks of the real χM′ and theimaginary χM″ parts of alternating current(AC) magnetic susceptibilities are observed at 2.2 K, indicated thatthe critical temperature Tcis 2.2 K.A very little hysteresis loop is observed with a small coercive fieldof 20 Oe. [ABSTRACT FROM AUTHOR]