The isomers of xylene have been separated by enclathration using three host compounds: 9,9'-bianthryl (H1), 9,9'-spirobifluorene (H2) and trans-2,3-dibenzoylspiro[cyclopropane-1,9-fluorene] (H3). The structures of each host with a single xylene isomer have been elucidated and, for H1, the relative lattice energies of the clathrates with ortho- and para-xylene have been evaluated.

The solid-liquid phase diagram of the (1-ethyl-3-methylimidazolium bis{(trifluoromethyl) sulfonyl} amide + benzene) system was determined and allowed us to identify and characterize an equimolar inclusion compound, [emim][NTf2].C6H6, with a congruent melting temperature: this type of behaviour, reported here for the first time, together with the X-ray structure of the inclusion compound lays em...

A competition of point defect configurations is inherent to crystalline phases increased structural complexity. Symmetry preserving phase transitions between them belong the special class isostructural transitions. Type-I silicon clathrates are complex whose unit cell containing a fifties atoms consists 3D covalent framework face-sharing polyhedral cages encapsulating guest cations. At high pre...

Introduction Type-I Si clathrates, whose general chemical formula is A8Si46, have a unique structure. In the compounds, Si atoms form Si20 dodecahedra and Si24 tetrakaidehedra, and these polyhedra are linked by shared faces. The A atoms are located in the center of the polyhedra. A search on the superconducting materials has been conducted in Si clathrates since discovery of superconducting ful...

Semiconducting group 14 clathrates are inorganic host-guest materials with a close structural relationship to gas hydrates. Here we utilize this inherent structural relationship to derive a new class of porous semiconductor materials: noble gas filled group 14 clathrates (Ngx[M136], Ng = Ar, Kr, Xe and M = Si, Ge, Sn). We have carried out highlevel quantum chemical studies using periodic Local-...