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This paper investigates the third-order nonlinear optical properties of two azo-nickel chelate compounds by the optical Kerr gate method at 830nm wavelength with pulse duration of 120 fs. Both of the two compounds exhibited large third-order optical nonlinearity. The second-order hyperpolarizability, γ, of Compound 1 is of 1.0 × 10−31 esu. Due to the charge transfer, the γ of Compound 2 with electron donor and acceptor group is 4.9 × 10−31 esu, which is a four-time enhancement in comparison with Compound 1. The absorption spectra show that the electron push–pull effect, which induces intramolecular charge transfer, leads to the increased optical nonlinearity.

A polymer/MoO3 layered structure can be obtained via a cooperative formation route by mixing the organic monomers with acidified ammonium molybdate. MoO3 deposits as a hydrolysis product of ammonium molybdate when the monomers begin to be polymerized. The polymer can be intercalated into MoO3 layers, and its polymerization will be made irreversible. The polymerization is thus accelerated and can go on synchronously with deposition of MoO3. As a result, a precipitation of layered polymer/MoO3 can be obtained as soon as the starting materials are mixed.

The phase diagram of Go-rich Sm-Go-Ti system was obtained by X-ray diffraction analysis and magnetic measurement. It was found that there exist three series of compounds, SmCo7-xTix, Sm2Co17-xTix and SmCo12-xTix. The formation ranges for these three series are 0.32 less than or equal tox less than or equal to0.54, 0 less than or equal tox less than or equal to1.13 and 1.45 less than or equal tox less than or equal to1.95, respectively. The 3:29 phase was not found after annealing Sm9.31Co90-xTix(3 less than or equal tox less than or equal to 15) prepared with an excess Sm of 15%, 20% and 25% added, at temperatures ranging from 1303 to 1403 K. It was also found that the Curie temperatures T-C and saturation magnetization M-s decrease with increasing Ti content for both SmCo12-xTix and Sm2Co17-xTix compounds. Below T-C, the uniaxial and planar anisotropies were observed for Sm2Co17-xTix and SmCo12-xTix compounds, respectively. The anisotropy fields B-a measured at 1.5 K for both SmCo12-xTix and Sm2Co17-xTix compounds as a function of Ti content exhibits a peak at certain compositions, which is thought to be associated with the preferential substitution of Ti for Co.