High-energy synchrotron x-ray diffraction for in situ diffuse scattering studies of bulk single crystals

High-energy synchrotron x-ray scattering offers a powerful technique for investigation of single-crystal material structures. Large, mm-sized crystals can be used, allowing complex in situ sample environments to be employed. Here, we demonstrate how this technique can be applied for the collection of single-crystal diffuse scattering volumes from the electro-active material 96%Bi0.5Na0.5TiO3-4%BaTiO3 while electric fields are applied in situ. The data obtained allow correlation of the atomic and nanoscale structures with the observed macroscopic electro-active properties of interest. This article presents a recent study relating the nanoscale stacking fault structure in BNT-BT to the relaxor-ferroelectric nature of the material [Daniels et al. in Appl. Phys. Lett. 98, 252904 (2011)], and extends this study with further experimental description and analysis.close1

Lithothamnin A, the first bastadin-like metabolite from the red alga Lithothamnion fragilissimum.

Lithothamnin A (1) is a new bastadin-like metabolite and represents the first report of this class of molecules from the red alga Lithothamnion fragilissimum. Lithothamnin A contains several novel structural features that distinguish it from other bastadins. These unique structural features include novel aromatic substitution patterns and the presence of a meta-meta linkage between aromatic rings, in addition to the meta-para linkage seen in the bastadins. Lithothamnin A is modestly cytotoxic in a panel of six human tumor cell lines