The title benzyl Grignard reagent, [Mg2Br2(C7H7)2(C4H10O)2], was obtained by reaction of benzyl bromide with magnesium in diethyl ether, followed by crystallization from toluene. The asymmetric unit comprises one half-molecule, the structural dimeric unit being generated by inversion symmetry with an Mg Mg distance of 3.469 (2) Å. The Mg(II) atom exhibits a distorted tetrahedral coordination ge...

We demonstrate the epitaxial growth of a metastable (with respect to the bulk) hcp crystal as well as any other close-packed stacking sequence of colloidal hard spheres. At certain stretched and compressed lattices we furthermore observed growth of a non-close-packed superstructure and of a perfect (100)-aligned fcc crystal. Perfect template-induced hcp-crystal growth occurs at lattice spacings...

Two-dimensional (2D) crystallization on solid surfaces is governed by a subtle balance of supramolecular and interfacial interactions. However, these subtle interactions often make the prediction of supramolecular structure from the molecular structure impossible. As a consequence, surface-based 2D crystallization has often been studied on a case-by-case basis, which hinders the identification ...

Recombinant Bacillus halmapalus alpha-amylase (BHA) was studied in two different crystal forms. The first crystal form was obtained by crystallization of BHA at room temperature in the presence of acarbose and maltose; data were collected at cryogenic temperature to a resolution of 1.9 A. It was found that the crystal belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 47.0, b ...

As a first step to gain insight into the structure of the rotavirus virion at atomic resolution, we report here the expression, purification, and crystallization of recombinant rotavirus protein VP6. This protein has the property of polymerizing in the form of tubular structures in solution which have hindered crystallization thus far. Using a combination of electron microscopy and small-angle ...

The crystallization of proteins makes it possible to determine their structure by X-ray crystallography, and is therefore important for the analysis of protein structure-function relationships. L2 lipase was crystallized by using the J-tube counter diffusion method. A crystallization consisting of 20% PEG 6000, 50 mM MES pH 6.5 and 50 mM NaCl was found to be the best condition to produce crysta...

This study addresses the crystallization and multiple melting behavior of a new high temperature semicrystalline polyimide, which is based on an ether diamine (TPER or 1,3 (4) APB) and BTDA dianhydride, both of which are commercially available. It also uses phthalic anhydride to endcap the chains thus improving thermal stability. The polyimide displays a Tg at ca. 230°C and two prominent meltin...

The first bent-core molecules comprising 4-iodoresorcinol as the central core unit and incorporating azobenzene units have been synthesized. A new type of dark conglomerate phase (DC phase) is observed, which remains over a wide temperature range down to room temperature without crystallization.

A modified version of the Gibbs-ensemble Monte-Carlo method reveals how polydisperse charged colloidal particles can build complex colloidal crystals. It provides general rules that are applicable to this fractionated crystallization that stems from size segregation. It explains the spontaneous formation of complex crystals with very large unit-cells in suspensions of nanoparticles with a broad...

Preparation of suitably large and well-ordered single crystals is usually the rate-limiting step in the determination of the three-dimensional structure of RNAs and their complexes with proteins by X-ray crystallography. This unit discusses a variety of experimental considerations for obtaining crystals of RNAs and RNA-protein complexes. Topics include design of crystallizable constructs, scree...