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The reaction of 2‐methylene‐1,3‐dioxolanes and 2‐methylene‐1,3‐oxazolidines with benzoyl peroxide (acceptor radical) and with N‐ethylmaleimide (acceptor) was investigated. It was shown that benzoyl peroxide adds to monomers 1a and 1b, giving the corresponding linear diester amides 1a and 1b respectively. The oxazolidine 1c adds benzoyl peroxide, without ring opening, by addition to the exomethylene group. Together with N‐ethylmaleimide the oxazolidines 1a or 1b produce deep‐colored charge transfer complexes, resulting in high molecular poly‐N‐ethylmaleimides probably via a radical mechanism. The 1,3‐dioxolanes 2a and 2b were radically polymerized to produce polyacetals by vinyl polymerization. 2c was polymerized to produce randomly containing acetal units and ester units. The mechanism of polymerization of 2e is complex, affording polymers of nonuniform character. 2‐Methylene‐4‐phenyl‐1,3‐dioxolane polymerization leads to polyester as the main structure, and to a lesser degree polyacetal structures. The chemical structures of the polymers were confirmed by NMR spectra and elemental analysis. © 1996 John Wiley & Sons, Inc.

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In atom lithography, neutral atoms are focused by laser light to form a periodic pattern on a substrate. We have realized two-dimensional structuring of chromium on a silicon substrate employing a polarization gradient light mask with uniform intensity. The generated structures exhibit peak-to-peak distances below half the laser wavelength. The results are explained by a theoretical model which takes into account the magnetic substructure of the atomic transition employed and the influence of a static magnetic field.