Confinement of halide ions within homologous inverse coordination hosts; modification of halide-ion selectivity

The structures of a series of spherical host-guest complexes [{MeE(PPh)(3)Li(4)·3thf}(4)(μ(4)-X)](-) (E = Al, [1X](-); E = Ga, [2X](-); E = In, [3X](-)) reveal that changing the halide ions (X = Cl, Br, or I) within their central tetrahedral Li(4) sites has negligible effect on the structural parameters.     

Ionic Liquids: New Perspectives for Inorganic Synthesis?

Ionic liquids are credited with a number of unusual properties. These include a low vapor pressure, a wide liquid‐phase range, weakly coordinating properties, and a high thermal/chemical stability. These properties are certainly of great interest for inorganic synthesis and the creation of novel inorganic compounds. On the other hand, the synthesis repertoire for preparing inorganic compounds has always been broad, ranging from syntheses in solutions and melts to solid‐state reactions, and from crystal growth in the gas phase to high‐pressure syntheses. What new aspects can ionic liquids then add to the synthesis of inorganic compounds? This Minireview uses some early examples to show that the use of ionic liquids indeed provides access to unusual inorganic compounds.     

App-based scaffolds for writing two-column proofs

This paper presents apps designed to assist students in understanding and developing proofs in geometric theorems. These technologies focus on triangle congruence, triangle similarity and properties of parallelograms. Focus group discussions and initial testing of the apps revealed that the apps offered a more engaging medium for learning proving and were capable of facilitating proof-writing skills in geometry.     

Initial incorporation of sulfur into the Pd(1 1 1) surface: A theoretical study

Density functional theory is used to investigate the initial inclusion of sulfur into the subsurface interstitial sites of Pd(1 1 1) surface. Pure subsurface adsorption is found to be less energetically favorable than on-surface adsorption. The incorporation of sulfur into the metal becomes more favorable than continuous adsorption on the surface after a critical on-surface sulfur coverage. We find subsurface sulfur occupation to be energetically favorable after adsorption of more than half a monolayer on the surface. Occupation of subsurface sites induces a pronounced structural distortion of the Pd(1 1 1) surface. We find significant expansion of interplanar spacing between the uppermost surface metal layers and rearrangement of the S overlayer. The interplay between the energy cost due to structural distortion of Pd(1 1 1) and the energy gain due to bond formation for different structures is discussed.     

Rational design of an inhibitor of dethiobiotin synthetase; interaction of 6-hydroxypyrimindin-4(3H)-one with the adenine base binding site

Modelling of the H-bonding interactions involved in the binding of the adenine base component of ATP to E. coli dethiobiotin synthetase (DTBS) suggested that 6-hydroxypyrimidin-4(3H)-one (6-HP4) should selectively bind to this site in the enzyme. Kinetic studies show that 6-HP4 is a competitive inhibitor of DTBS and x-ray crystallography shows that 6-HP4 binds specifically in the purine base binding site of the enzyme.