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The article describes a new novel class of Reversible chain Transfer catalyzed polymerizations (RTCPs) with germanium, tin and phosphorus catalyst. These catalysts are widely used because of their low toxicity and low costs.

Organostibines serve as excellent mediators for living radical polymerization (LRP). Furthermore, the generation of ethyl radical from triethylstibine was demonstrated by an electron spin resonance spectroscopic study.

A report that MX-chain complex [NiBr-(chxn)2]Br2 is different from the charge-density-wave (CDW) complexes is presented. In this complex, an unpaired electron in the Ni(super 3+)3d(sub z)2 orbital is strongly localized on the Ni atom owing to the strong electron correlation.

Living radical polymerization (LRP) is recognized as a powerful method to synthesize nanostructural macromolecules with defined structures possessing various functional groups, which are not compatible with ionic or metal-catalyzed polymerization conditions. Organotellurium-mediated living radical polymerization (TERP) is a new class of LRP, which shows versatility, molecular weight controllability, functional group compatibility and ease of polymer-end transformation.

In the field of solid-state chemistry and physics, there is much interest in one-dimensional (1-D) electron systems because pronounced phenomena characteristic of 1-D systems have been observed such as the Haldane gap in integer spin antiferromagnetic compounds, solitons and polarons observed in ru-conjugated polymers, slow relaxation of magnetization in several ferromagnetic and ferrimagnetic compounds known as single-chain-magnets. Halogen-bridged 1-D metal complexes (MX-chains) also have been attractive targets because of the highly isolated 1-D chain structure and the variety of the electronic states which can be tuned by substituting those components. MX-chain complexes with a mixed-valence structure have been widely studied as 1-D materials with strong electron-lattice interactions.

Photocontrolled organocatalyzed living radical polymerization was conducted over a wide range of irradiation wavelengths (350-750 nm). The polymerization was induced and controlled at the desired wavelengths by exploiting suitable organic catalysts. This system was finely responsive to the irradiation wavelength; the polymerization was instantly switched on and off, and the polymerization rate was sensitively modulated by altering the irradiation wavelength. The polymer molecular weight and its distribution (M(w)/M(n) = 1.1-1.4) were well controlled for methacrylate monomers up to fairly high conversions in many cases. The monomer scope encompassed various functional methacrylates, and their block copolymers were obtained. The feasibility of such a wide range of wavelengths and the fine response to the wavelength are unprecedented features. As a unique application of the wavelength-responsive nature of this system, we demonstrated "one-pot" selective regulation of living radical polymerization and another type of polymerization (ring opening polymerization), where the regulation was achieved by simply altering the irradiation wavelength. Facile operation and applicability to a wide range of polymer designs are advantages of this polymerization.