Photochemical Transformations with Iodine Azide after Release from an Ion‐Exchange Resin

This report discloses the photochemical homolytic cleavage of iodine azide after its formation following release from polymer‐bound bisazido iodate(I) anions. A series of radical reactions are reported including the 1,2‐functionlization of alkenes and the unprecedented chemoselective oxidation of secondary alcohols in the presence of primary alcohols.     

Toward high-performance computational chemistry: I. Scalable Fock matrix construction algorithms

Several parallel algorithms for Fock matrix construction are described. The algorithms calculate only the unique integrals, distribute the Fock and density matrices over the processors of a massively parallel computer, use blocking techniques to construct the distributed data structures, and use clustering techniques on each processor to maximize data reuse. Algorithms based on both square and row-blocked distributions of the Fock and density matrices are described and evaluated. Variants of the algorithms are discussed that use either triple-sort or canonical ordering of integrals, and dynamic or static task clustering schemes. The algorithms are shown to adapt to screening, with communication volume scaling down with computation costs. Modeling techniques are used to characterize algorithm performance. Given the characteristics of existing massively parallel computers, all the algorithms are shown to be highly efficient for problems of moderate size. The algorithms using the row-blocked data distribution are the most efficient. © 1996 by John Wiley & Sons, Inc.     

Organoborane-mediated synthesis of functional polymers: A review

This article reviews recent advances in the synthesis of polar functional polymers via the mediation of organoborane monomers and polymers. Both direct polymerization and post-polymerization functionalization processes are described. Organoborane-assisted Ziegler–Natta, metathesis, and hydroboration (haloboration) polymerizations are presented. Moreover, the special problems and opportunities of polymer modification of olefin containing homo and copolymers by organoboranes are discussed.     

Polymerforschung und -technologie im Iran

Im Laufe der letzten Jahre wurden - von den meisten westlichen Fachkollegen unbemerkt - an mehreren iranischen Universitäten und Forschungsinstituten Abteilungen eingerichtet, die sich in Forschung und Lehre mit Chemie, Physik, Anwendungs- und Verfahrenstechnik der Polymere beschäftigen. Das 1986 gegründete Polymer Research Center of Iran organisierte im Mai dieses Jahres das 1. Internationale Seminar.     

On the Influence of the Distortion Distribution on the Determination of Roentgenographic Particle Sizes and Distortions (II) Distortion Distributions and Evaluation Procedure

It is shown that a Gaussian distribution of the distortion not enables in each case an exact evaluation of experimentally measured Debye-Scherrer lines. – After a discussion of simple possibilities for set up of simple and more common distortion distributions with more than one free parameter is given a procedure independent on the distortion distributions for the determination of roentgenographic particle sizes and distortions.     

The crystal structure of 1-anilino-3-phenylimino propene-(1), C15H14N2

The 1-Anilino-3-phenylimino propene-(1) crystallizes in the Iba2 space group having the lattice constants a = 20.132 Å; b = 16.102 Å; c = 7.683 Å. The elementary lattice cell contains 8 molecules. The intensities were measured by means of an automatic fourcircle diffractometer. The structure was clarified by a direct phase determination. The refinement was carried out by means of the least squares method for 1532 symmetryindependent reflections up to an R-value of 0.10. The molecular structure is more similar to that of the asymmetric polymethine merocyanines, and less to the symmetrical polymethine cyanines. This is due to the different electronic structure of the amino and imino groups in the molecule. The molecules are electrically neutral. The intermolecular contacts are made through N-H…N hydrogen bridges and van-der-Waals contacts between C- and H-atoms.