The concept of oxidation states (OS) is widely used in all disciplines of physical sciences to explain and predict properties and phenomenons. Its definition stems from a simple ionic charge transfer mechanism and lacks justification in systems with covalent or metallic characters. In fact it has been shown that in some transition metal complexes charge transfer does not occur upon changing the...

We introduce the notion of a compressed pseudo-lattice and suggest its use as a data structure in areas of application related to Formal Concept Analysis. It is closely related to the line diagram of a lattice and its use as a computational tool in applications such as machine learning, information retrieval and knowledge discovery in databases is discussed. The data structure, essentially a bi...

The Calculus of Reenements (COR) presented here takes this idea of types as spec-iications and subtyping as reenement and pushes it to an extreme. Types and values are no longer distinguished; in COR we consider a unique hierarchy of objects. A good way to deal with the hierarchy of objects is to structure it as a complete lattice. And if functions are to be considered as rst class citizens in ...

We analyze the t−J model on a square lattice using bosonic spinons and fermionic holons. Spinons are paired into singlets, which condense below a temperature T ∗. Metallic conduction and d-wave superconductivity result from separate, sublattice-preserving, holon hopping processes which originate from coupling with the condensate. Holons form a charge Fermi liquid, becoming incoherent (confined)...

A new organic-inorganic hybrid material, {(C7H10NO)[BiI4]·2H2O} n , has been synthesized by slow evaporation of an aqueous solution at room temperature. The anionic sublattice of the crystal is built up by [BiI6] octa-hedra sharing edges. The resulting zigzag chains extend along the a-axis direction and are arranged in a distorted hexagonal rod packing. The p-anisidinium cations and the water m...

A three-dimensional layered Ising-Antiferromagnet with a ferromagnetic intra-layer coupling to z neighbors, zJ > 0, and an antiferromagnetic interlayer coupling to z neighbors, zJ ′ < 0, is investigated by Monte Carlo simulations on a hexagonal lattice. The physical nature of the anomalous temperature bahavior of the sublattice magnetizations, which is found for certain values of r = zJ/zJ ′ an...

Powders of silver sulfide have been synthesized by chemical bath deposition from aqueous solutions of silver nitrate and sodium sulfide in the presence of sodium citrate or EDTA-H2Na2. Colloid solutions have been prepared by a chemical condensation method from the same aqueous solutions. Synthesized silver sulfide nanopowders have a monoclinic (space group P21/c) acanthite-type structure but th...

Combining a semiclassical analysis with exact diagonalizations, we show that the ground state of the SU(3) Heisenberg model on the square lattice develops three-sublattice long-range order. This surprising pattern for a bipartite lattice with only nearest-neighbor interactions is shown to be the consequence of a subtle quantum order-by-disorder mechanism. By contrast, thermal fluctuations favor...