Inclusion of thiourea guest molecules in the tridimensional spin crossover porous coordination polymers {[Fe(pyrazine)[M(CN)(4)]} (M = Pd, Pt) leads to novel clathrates exhibiting unprecedented large thermal hysteresis loops of ca. 60 K wide centered near room temperature.

Although clathrate materials are known for their small thermal conductivity, they have not shown a large thermoelectric power factor so far. We present the band structures of type VIII Si, Ge, and Sn clathrates as well as the alkali and alkaline-earth intercalated type VIII Si clathrates. Our calculations revealed that this group of materials has potentially large power factors due to the exist...

Clathrates are materials containing closed polyhedral cages stacked to form crystalline frameworks. With Si, Ge, and Sn atoms populating these frameworks, a wide variety of electronic and vibrational properties can be produced in these materials, by substitution upon framework sites or through incorporation of ions in cage-center positions. Commonly-formed structures include the type I, type II...

Although clathrate materials are known for their small thermal conductivity, they have not shown large thermoelectric power factor so far. We present the band structures of type VIII Si, Ge, and Sn clathrates as well as the alkali and alkaline-earth intercalated type VIII Si clathrates. Our calculations revealed that this group of materials have potentially large power factor due to the existen...

Keywords: Type-VIII clathrate Ba 8 Si 46 Ba 8 Al 16 Si 30 Density functional theory Lattice dynamics a b s t r a c t We present the results of first principles calculations of the structural, electronic, elastic, vibrational, and thermodynamic properties of the hypothetical silicon-based, guest containing type-VIII clathrates Ba 8 Si 46 and Ba 8 Al 16 Si 30. We obtained the lattice constant, fo...

Framework substitution has not been widely reported among the type-II group-IV clathrates. We have performed a theoretical study of the Cs8Ga8Si128 and Rb8Ga8Si128 clathrates, using the local-density approximation LDA to density-functional theory. In Rb8Ga8Si128 and Cs8Ga8Si128, eight Si atoms are substituted by Ga at the 8a crystallographic sites of the framework. We predict that both Rb8Ga8Si...

Methylviologen dication is easily reduced to a monocation radical, and turned to be blue, forming a charge-transfer complex with a donor molecule. Yoshikawa et al. recently reported photo-induced reduction and charge transfer complexes in polycyano–polycadmate host clathrates. We study this reduction using quantum chemical calculations. The energy changes with the torsion angle of the two catio...