For binary ionic compounds the Madelung energy can be calculated using the Madelung constant, the ionic charges and the next neighbour distance of the ions only. For ternary and higher systems the well-known standard formula cannot be applied, because the ionic charges and distances combine in different ways. In the present work we calculate the Madelung energy of the quaternary elpasolite stru...

A series of Ba1-x-ySrxCayTiO3 compounds were prepared with varying average ionic radii and cation disorder on A-site. All samples showed typical ferroelectric behavior. A simple empirical equation correlated Curie temperature, TC, with the values of ionic radii of A-site cations. This correlation was related to the distortion of TiO6 octahedra observed during neutron diffraction studies. The eq...

Ionic liquids − defined as salts with a melting point below 100 ◦C – date back to 1914, when Paul Walden reported on [C2H5NH3][NO3], a salt with a melting point of +12 ◦C. While Walden was surely ahead of his time, ionic liquids made an impressive development during the last 10 years. This is due to their unique portfolio of properties: high temperature stability (in favourable cases up to 400 ...

The chemistry of the chalcogen azides has been well investigated in the last years [1]. Among the various possible oxidation states of the chalcogens, selenium(IV) and tellurium(IV) possess the highest stability, and the ionic chalcogen(IV) azides [R3Te]N3 and [R3Se]N3 have been described and thoroughly characterized recently [2, 3]. In addition, the first telluronium, selenonium and sulfonium ...

Recently, it has been found that room-temperature ionic liquids can be used as stable, unusual selectivity stationary phases. They show "dual nature" properties, in that they separate nonpolar compounds as if they are nonpolar stationary phases and separate polar compounds as if they are polar stationary phases. Extending ionic liquids to the realm of chiral separations can be done in two ways:...

michael addition of pyrimidine and purine nucleobases to substituted as well as unsubstituted α,β-unsaturated esters efficiently proceeds in the presence of catalytic amount of zinc oxide in ionic liquid 1-butyl-3-methylimidazolium bromide (zno/[bmim]br) under microwave irradiation to afford carboacyclic nucleosides, as biologically important compounds, in good to excellent yields and in short ...

1. evaluate the adsorbability of polar/ionic pesticides and ionic degradates on activated carbon, 2. determine polar/ionic pesticide and ionic degradate breakthrough behavior in granular activated carbon (GAC) adsorbers, 3. develop recommendations for drinking water utilities regarding GAC adsorber design and operation parameters, and 4. evaluate different adsorption test methods in relation to...