A Nanometer-Sized High-Spin Polyradical:  Poly(4-phenoxyl-1,2-phenylenevinylene) Planarily Extended in a Non-Kekulé Fashion and Its Magnetic Force Microscopic Images

A π-conjugated, but non-Kekulé- and nondisjoint-type poly(1,2-phenylenevinylene) network bearing 4-substituted di-tert-butylphenoxyls was synthesized through a one-pot polycondensation of the star-shaped subpart and the subsequent oxidation, which was persistent even at room temperature. The polyphenoxyl radical with a spin concentration of 0.4 displayed an average S of 10/2. The polyradical with the molecular weight of 3.2 × 10⁴ gave a disklike image of ca. 35 × 0.6 nm with both an atomic and a magnetic force microscopy:  the molecular image was examined as a nanoscale and single-molecular-based magnetic dot.