KNi3(AsO4)(As2O7)

The structure of the title compound, potassium trinickel arsenate diarsenate, is built up from corner‐ and edge‐sharing NiO₆ octahedra, AsO₄ tetrahedra and As₂O₇ groups, giving rise to a polyhedral connectivity which produces large tunnels running along the crystallographic [010] direction. The K⁺ cations are located within these tunnels.     

Equilibrium pricing bounds on option prices

We consider the problem of valuing European options in a complete market but with incomplete data. Typically, when the underlying asset dynamics is not specified, the martingale probability measure is unknown. Given a consensus on the actual distribution of the underlying price at maturity, we derive an upper bound on the call option price by putting two kinds of restrictions on the pricing probability measure. First, we put a restriction on the second risk-neutral moment of the underlying asset terminal value. Second, from equilibrium pricing arguments one can put a monotonicity restriction on the Radon-Nikodym density of the pricing probability with respect to the true probability measure. This density is restricted to be a nonincreasing function of the underlying price at maturity. The bound appears then as the solution of a constrained optimization problem and we adopt a duality approach to solve it. Explicit bounds are provided for the call option. Finally, we provide a numerical example.     

Crystal structure, thermal analysis and IR spectrometric investigation of L-tyrosine hydrazide sulfate

Chemical preparation, X-ray single crystal, thermal analysis and IR spectrometric investigation of (C₉H₁₅N₃O₂)SO₄ denoted LTHS are described. The LTHS crystallizes in the monoclinic system with P2₁ space group. Its unit cell dimensions are a=5.5386(1) Å, b=8.0467(4) Å, c=14.0780(6) Å, β=93.339(3)° with V=626.36(4) Å³ and Z=2. The structure has been solved using direct method and refined to a reliability R factor of 0.0212. The LTHS structure is built up from organic chains parallel to the b axis, linked via N---H…O hydrogen bonds and interconnected by inorganic groups so as to build a three-dimensional arrangement.     

Layered zincoarsenate templated by N,N,N′,N′‐tetra­methyl­ethyl­ene‐di­amine mol­ecules

The title compound, N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammon­ium di­aqua­(arsenate)­(hydrogen arsenate)­dizinc(II), (C₆H₁₈N₂)_0.5[Zn₂(AsO₄)(HAsO₄)(H₂O)₂], is a new zincoarsenate obtained by hydro­thermal synthesis. The structure consists of infinite two‐dimensional anionic layers alternating with planes containing centrosymmetric organic diprotonated template N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammonium cations, [H₃N­C₆H₁₂NH₃]²⁺. The latter are interconnected to the framework through hydrogen bonds.