Switching the Conformation of 3,2′:6′,3″-tpy Domains in 4′-(4-n-Alkyloxyphenyl)-3,2′:6′,3″-Terpyridines

The preparation and characterization of 4′-(4-n-octyloxyphenyl)-3,2′:6′,3″-terpyridine (8) and 4′-(4-n-nonyloxyphenyl)-3,2′:6′,3″-terpyridine (9) are reported. The single crystal structures of 4′-(4-n-hexyloxyphenyl)-3,2′:6′,3″-terpyridine (6), 4′-(4-n-heptyloxyphenyl)-3,2′:6′,3″-terpyridine (7), and compounds 8 and 9 have been determined. The conformation of the 3,2′:6′,3″-tpy unit is trans,trans in 6 and 7, but switches to cis,trans in 8 and 9. This is associated with significant changes in the packing interactions with a more dominant role for van der Waals interactions between adjacent n-alkyloxy chains and C–Hmethylene... π interactions in 8 and 9. The solid-state structures of 6 and 7 with the n-hexyloxy and n-heptyloxy chains feature interwoven sheets of supramolecular assemblies of molecules, with pairs of n-alkyloxy chains threaded through cavities in an adjacent sheet.

Hodgesmithite, (Cu,Zn)6Zn(SO4)2(OH)10·3H2O, a new copper zinc sulfate mineral with a unique, decorated, interrupted-sheet structure

Hodgesmithite, ideally (Cu,Zn)6Zn(SO4)2(OH)10·3H2O, is a new copper zinc sulfate mineral from the Block 14 Opencut, Broken Hill, New South Wales, Australia. Electron microprobe analysis provided the empirical formula Cu4.84,Zn2.16,Cd0.04[(SO4)1.89,(SiO4)0.12]2.01(OH)9.82·3.15H2O based on 21 oxygen atoms per formula unit. Hodgesmithite is trigonal, space group P3, with a = 8.1905 (12), c = 7.0990 (14) Å, V = 412.43 (12) Å3 and Z = 1. The crystal structure of hodgesmithite, R 1 = 0.0272 for 5145 reflections with F o > 4σ(F o) measured with synchrotron X-ray radiation (λ = 0.71080 Å), contains interrupted sheets of edge-sharing Cu(O,OH)6 octahedra in the (001) plane. Every seventh octahedral site is vacant and capped by a ZnO4 tetrahedron and an SO4 tetrahedron which are attached to the sheet above and below this position. The sheets are additionally decorated on one side by SO4 tetrahedra that share a vertex incident to three Cu—O(apical) bonds. Interstitial H2O groups lie between the sheets. ZnO4 tetrahedra share vertices with SO4 tetrahedra from the adjacent sheet to provide linkage between the sheets in the c direction.

A New Composite-Sample Method for Orientation-Distribution Analysis

A new composite-sample method is suggested for crystallite orientation distribution analysis. The proposed method entails preparation of composites such that the surface to be examined is perpendicular to the rolling direction. The suggested reference frame is (—ND, TD, RD) for Roe's method. This choice simplifies expression of the results with respect to the conventional (RD, TD, ND) frame. A novel technique employing laser welding on three surfaces is used to bond adjacent sheet layers. The proposed composite-sample can be more easily and accurately constructed. It requires only about 12 percent of the material needed for Lopata and Kula's method. Existing programs for incomplete pole-figures have been modified to permit application of the new method. The method is expected to be statistically advantageous where materials develop “pancake”- or acicular-shaped grains. The method is illustrated for a deep-drawing aluminum-killed sheet steel, and results are compared with those obtained with a conventional sheet-sample.