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Two novel three-dimensional metal-coordination polymers [Cd2(L)4(μ2-X)(X)(H2O)]n [X = Cl (1) and Br (2)] have been solvothermally synthesized by the self-assembly of an unsymmetric bridging ligand, [L = 2-(1H-imidazol-1-ylmethyl)-1H-benzoimidazole], and cadmium salts with different anions, respectively. The two complexes are isostructural and exhibit an acentric sqp-net, in which the cadmium ions act as unusual five-connected nodes. The induction of the flexible and unsymmetric ligand leads them to crystallize in a noncentrosymmetric polar packing arrangement, which displays a second harmonic generation response and ferroelectric behaviors.

One new one-dimensional neutral coordination polymer [Zn(BTA)2(H2O)]n (1) was hydrothermally synthesized by the self-assembly of the flexible and unsymmetric bridging ligand, 2-(1H-benzotriazol-1-yl)acetic acid, and zinc nitrate. The induction of the unsymmetric ligand leads it to crystallize in non-centrosymmetric polar packing arrangement, which displays second harmonic generation response and ferroelectric behavior, which provides a new strategy for designing functional coordination compounds.

Aluminum (Al3+)-doped Pb(Mg1/3Nb2/3)O3-30PbTiO3 (PMN-30PT) solid solution piezo-crystals were grown by a top-seeded solution growth method. The dielectric, piezo-, and ferro-electric properties were characterized. A dispersive maximum of dielectric permittivity was found around TC = 135 °C, which does not depend on frequency. Interestingly, the rhombohedral-tetragonal phase transition, which appears at 60 °C in pure PMN-PT and thereby causes the depoling of the crystals at a relatively low temperature, has been increased to 105 °C by means of the Al3+-doping. This extends the upper limit of application temperature for electromechanical transducers up to the TC. The piezoelectric coefficient (d33) was found to be 2000 pC/N at room temperature. The longitudinal electromechanical coupling factor k33 reaches 85−90%, which shows a good thermal stability upon heating up to 135 °C. The peak to peak bipolar strain was measured to be 0.25% at an electric field of up to 17 kV/cm.

By combination of Nb5+ (having a d0 electronic configuration) and the lone-pair-containing iodate anion, a new SHG material, BaNbO(IO3)5, has been prepared. It exhibits a very large SHG response (∼14 times that of KH2PO4 and ∼660 times that of α-SiO2) and is phase-matchable. The material has high thermal stability and a wide transparent region.

By combination of Nb(5+) (having a d(0) electronic configuration) and the lone-pair-containing iodate anion, a new SHG material, BaNbO(IO(3))(5), has been prepared. It exhibits a very large SHG response (approximately 14 times that of KH(2)PO(4) and approximately 660 times that of alpha-SiO(2)) and is phase-matchable. The material has high thermal stability and a wide transparent region.