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To mimic superoxide dismutase, two new copper(II) complexes, [Cu(bqad)X2] (1, X = Cl; 2, X = Br; where bqad = N,N′-bis(2-quinolinylmethyl)amantadine), have been synthesized and characterized by elemental analysis, electronic absorption, IR and single crystal X-ray diffraction. The copper ions in 1 and 2 have a penta-coordination geometry, composed of three nitrogen atoms from one bqad ligand and two halide anions. The complexes showed quasi-reversible one-electron Cu(II)/Cu(I) redox waves, as determined by cyclic voltammetry. By using an NBT assay at pH 7.8, the superoxide dismutase (SOD)-like activity (IC50) of 1 and 2 were measured to be 0.43 and 0.32 μM, respectively. The enhancement in the SOD-like activity of 2 can be ascribed to the formation of the species [Cu(bqad)2(H2O)2]2+ in aqueous solution due to the two labile bromine ions. Furthermore, DFT calculations were performed in order to understand the relationship between the structures and activities of the mimics.

To mimic the active site of Cu,Zn-SOD, new copper(II) complexes (1, [Cu2(HL)2(L)2](ClO4)2; 2, [Cu(HL)2(phen)](ClO4)2; where HL = (N-methyl-2-methylol)imidazole, phen = 1,10-phenanthroline) have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. Copper(II) in 1 is four-coordinate by a N2O2 plane with two copper(II) ions bridged with two oxygens from the deprotonated hydroxylmethyl pendants. Each Cu2+ in 2 is coordinated by four nitrogens from two HL and one co-ligand of 1,10-phenanthroline. Electrochemistry of the complexes was studied by cyclic voltammetry. The atomic net charges distribution and frontier molecular orbital energies were obtained by Gaussian 98 program with DFT method at B3LYP/lanl2dz level. The SOD-like activity (IC50) of 1 and 2 were measured as 0.10 ± 0.01 and 0.19 ± 0.01 μM by NBT assay at pH 7.8. The higher SOD activity of 1 could be attributed to the coordination configuration and the labile hydroxymethyl pendants.

The dinuclear complex [Cu2(HL)2(H2O)2](ClO4)2 (1) [H2L = 5′-(pyridin-2-yl)-1-H,2′-H-3, 3′-bis(1, 2,4-triazole)] was obtained and fully characterized. It exhibits a centrosymmetry configuration, in which each copper(II) ion is pentacoordinate with four nitrogen atoms of two triazole ligands and one oxygen atom from a water molecule. The net atomic charges distribution and atomic orbital contribution to frontier molecular orbitals were obtained using the Gaussian 98 program with Hartree-Fock method at LANL2DZ level, indicating that the copper(II) ion has the potential to accept the electron of O2·–. The complex showed quasi-reversible one-electron CuII/CuI redox waves with redox potentials of –0.034 V. The SOD-like activity (IC50) of 1 was measured to be 0.18 ± 0.01 μM by xanthine/xanthine oxidase-NBT assay at pH 7.8. The relatively high SOD activity suggests that the positive charge of protonated triazole can effectively steer O2·– to and from the active copper ion.

We show that Cu ions doped in (${\mathrm{K}}_{\mathit{x}}$${\mathrm{Na}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${)}_{0.4}$(${\mathrm{Sr}}_{\mathit{y}}$${\mathrm{Ba}}_{1\mathrm{\ensuremath{-}}\mathit{y}}$${)}_{0.8}$${\mathrm{Nb}}_{2}$${\mathrm{O}}_{6}$ (KNSBN) form two energy levels in the band gap, which increase the effective charge-combination-center concentration ${\mathit{N}}_{\mathrm{eff}}$. The two-wave coupling gain and the response speed of KNSBN crystals are increased while the photoconductivity and the effects of a dc field on the photorefractive properties are reduced. Self-pumped phase conjugation (SPPC) experiments have revealed that the effects of Cu ions on the photorefractive properties have a wavelength dependence. The SPPC response time at the ${\mathit{e}}^{\mathrm{\ensuremath{-}}1}$ level can be shortened to 200 ms.

Four faces of TGS crystal were chosen to study the growth kinetics. BCF spiral growth mechanism for the surface diffusion model was analyzed using the kinetic data of the four faces. We found it is more important that the growth units enter the surface layer to grow after overcoming the dehydration activation energy, than the process of surface diffusion. Two simple crystal forms of TGS spontaneousnucleation crystals were also observed.

The energy levels of Pr￣(3+) in SBN crystal are determined by means of absorptionspectra and fluorescence spectra. The fluorescence band exhibits a double peak dueto Pr￣(3+) ions at different sites in SBN crystal.This shows that the multiphoton rel-axation of ￣3P_0→￣1D_2 plays a dominant role in the radiationless transition of ￣3P_0 stateof Pr￣(3+) ion by analysing the relation between the fluorescencc lifetime and the sa-mple temperature.