| The various structures of transition metal complexes show abundant content on magnetic research. The syntheses, crystal structures and magnetic properties of novel transition metal complexes not only have meanings on subjects of theoretic research, but also possess applied prospect.In this thesis, nine novel transition metal complexes, which were ligated with 2,2'-dipyridylamine (dpa), azido anion (N3-), dicyandiamido anion(C2N3-) or polyoxometalate anions, have been synthesized, and all of them were studied by Elemental Analysis, IR, TG-DTA and the variable-temperature magnetic susceptibility data.1. In a mixture of methanol and water solution, three novel 1-D cobalt (II) and nickel (II) complexes with azido-bridge, [Co(dpa)(N3)2] (1), [Co(dpa)(N3)2·H2O] (2) and [Ni(dpa)(N3)2·H2O] (3) have been synthesized. Complex (1) consists of 1-D stretched zig-zag neutral chain in which each cobalt (II) cation are alternatively bridged by two end-on (EO) and two end-to-end (EE) azido bridges. Complexes (2) and (3) are the iso-structural crystals, and both of them exhibit 1-D chain with cobalt(II) ions. The adjacent cobalt ions are built via three EO and one EE azido bridges. The study of the magnetic properties reveals dominating antiferromagnetic interactions between Ni(II) ions through the EE bridges. The best set of parameters found are: J1/kB = -33.4(2) K, g = 2.22(1) and Cimp = 0.048 cm3K/mol (4.8 % of an S = 1 spin).2. Two novel dinucler complexes [Cd(dpa)2(N3)2]2 (4) and [Zn(dpa)(N3)(CH3COO)]2 (5) with azido-bridge have been synthesized. Both (4) and (5) link the unit of [Cd(dpa)2(N3)2] and [Zn(dpa)(N3)(CH3COO)] through double EO bridges, respectively. Each metal center possesses an octahedral geometry.3. In a mixture of methanol and water solution, three novel complexes Mn(dpa)2(N3)2 (6), Fe(dpa)2(N3)2 (7) and Zn(dpa)2(dca)2 (8) have been synthesized. In all of them, six nitrogen atoms complete the metal center M(II) (M = Mn, Fe, Zn) coordination, showing an octahedral geometry, respectively.4. One novel complex [Cu(dpa)2]2V4O12 (11) supported by [V4O12]4– has been synthesized. Furthermore, three complexs {[M(dpa)2]2V4O12}·H2O [M = Co (9),Ni (10)] and (11) have been reviewed in detail. (9), (10) and (11) are composed of a [V4O12]4- ring bounded to two [M(dpa)2]2+ ( M = Co, Ni, Cu) moieties through the terminal oxygen atoms. In all of them, the distortion of cluster [V4O12]4– is different. (9) and (10) respective contain four vanadium atoms, and the average deviation from the plane defined by them are 0.0202 and 0.0164?, respectively. However, in (11), four vanadium atoms are almost coplanar.
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