Entanglement in Ising Chain with Inhomogeneous Magnetic Field

We have numerically calculated the thermal entanglement of a two-qubit system at low temperatures in a isotropic Ising chain under an inhomogeneous magnetic field. It is shown that in the homogeneous magnetic field, the two- qubit system has entangled states. It is concluded that the presence of the inhomogeneity in the magnetic field plays an effective role on the entangled states. Finally, it is suggested that the inhomogeneity in the magnetic field can be used to create two separated entangled formations in a two-qubit system.     

Synthesis,Crystal Structure,IR Spectra and Thermal Analysis of Na[Ag(sac)2] (sac = saccharinate)

The reaction of silver nitrate with sodium saccharinate (Na[sac]) in the presence of 2-pyridinepropanol in aqueous solution yields the title complex, Na[Ag(sac)₂]. The compound crystallizes in the triclinic space group [a = 8.0481(6), b = 9.0587(6), c = 11.1642(8) Å; α = 100.064(3), β = 99.917(3) and γ = 92.367(3)°, Z = 2]. The structure consists of Na⁺ and [Ag(sac)₂]^- ions, in which each silver(I) ion is doubly bridged by the sac ligands, exhibiting a distorted 'T' shaped AgN₂O coordination arrangement with one long [Ag-O_sulfonyl = 2.6390(10) Å] and two shorter bonds [Ag-N = 2.1405(11) and 2.1570(11) Å]. The coordination around silver(I) is trigonal planar and the N-Ag-N bond angle is 158.99(5)°. The Na⁺ ion is five-coordinate with two carbonyl and three sulfonyl O atoms of the adjacent sac ligands and acts as a bridge between [Ag(sac)₂]^- units, resulting in a three-dimensional network. The i.r. spectra and thermal decomposition behaviour of Na[Ag(sac)₂] are discussed in detail.     

A Three—Dimensional Lead(II) Polymer with Bridging Saccharinate and Unusually Coordinated Acetate Ligands — Synthesis,IR Spectra,and Crystal Structure of [Pb(H2O)(μ‐OAc)(μ‐sac)]n

The complex [Pb(H₂O)(μ‐OAc)(μ‐sac)]n with acetate (OAc) and saccharinate (sac) ligands was characterized by IR, elemental analysis and X‐ray crystallography. The mixed‐anion lead(II) complex crystallizes in the triclinic crystal system with the space group of P1¯. The single crystal X‐ray analysis shows that the complex is a coordination polymer in which the lead(II) ions have a highly distorted pentagonal bipyramidal coordination geometry. Lead(II) ions are bridged by carboxylate groups in a zigzag arrangement forming one‐dimensional infinite chains, which are also linked by sac bridges and aromatic π‐π contacts between the adjacent phenyl rings of sac ligands, resulting in a three‐dimensional network. One water molecule coordinates the lead(II) ion and also forms weak hydrogen bonds with the sulfonyl oxygen atoms of the neighboring sac ligands. The sac ligand acts as a bridging ligand through the nitrogen and carbonyl oxygen atoms, while the carboxylate moiety of the acetate ligand shows an unusual (bidentate, and bridging) coordination behaviour, which was observed for the first time in the structure.     

Adsorption of 2,2′-bipyridyl onto sepiolite,attapulgite and smectite group clay minerals from anatolia: The FT-IR and FT-Raman spectra of surface and intercalated species

The adsorption of 2,2-bipyridyl by natural sepiolite, attapulgite, hectorite, saponite and natural and ion exchanged (Mn, Fe, Co, Ni, Cu, Zn or Sn) bentonites has been investigated by FT-IR and FT-Raman spectroscopy. Spectroscopic results indicate that most of the adsorbed molecules are coordinated to either exchangeable cations (in the case of smectite group clays) or Lewis acidic centres (in the case of sepiolite and attapulgite) as bidentate ligands. The formation of monoanionic surface species has also been detected, to a relatively small extent. No physisorbed surface species has been observed. XRD patterns and UV-visible spectra of the samples are also recorded for additional information.Author for correspondence.     

Trans‐bis(saccharinato)cadmium(II) Complexes with 2‐Pyridylethanol: Synthesis,Crystal Structures,Spectral and Thermal Characterization of [Cd(sac)2(pyet)2] and [Cd(sac)2(H2O)(dmso)(pyet)]

Two trans saccharinate (sac) complexes of cadmium(II) with 2‐pyridylethanol (pyet) were synthesized and characterized by elemental analyses, FT—IR spectroscopy, thermal analysis and single crystal X‐ray diffractometry. The [Cd(sac)₂(pyet)₂] ( 1 ) and [Cd(sac)₂(H₂O)(dmso)(pyet)] ( 2 ) complexes crystallize in the monoclinic (P2₁/c) and orthorhombic [P2₁2₁2₁] crystal systems, respectively. The sac ligands in both complexes are N‐coordinated and located in trans positions, while the pyet molecules act as a bidentate N‐ and O‐donor ligand forming two six‐membered chelate rings. Thermal decomposition of the complexes in air results in elimination of aqua, dmso and pyet ligands, respectively, forming cadmium saccharinate as a stable intermediate, which also decomposes at higher temperatures to give cadmium oxide.     

Phenyliodine(V) fluorides

The known compound phenyltetrafluoroiodine(V) is shown by X-ray diffraction to have a tetragonal pyramidal structure with an apical phenyl group. This structure is compared to that of IF(OTeF₅)₄, where the apical position is occupied by the fluorine atom. C₆H₅IF₄ adds F⁻, forming C₆H₅IF₅⁻, which has a pentagonal pyramidal structure with an apical phenyl group. Fluoride abstraction from C₆H₅IF₄ by SbF₅ results in the formation of the cation C₆H₅IF₃⁺, which has a pseudotrigonal bipyramidal structure with the phenyl group occupying an equatorial position. Isoelectronic C₆H₅IOF₂ has a similar structure, with the phenyl group and oxygen atom both occupying equatorial positions.     

An infrared and raman spectroscopic investigation of copper(II) tetracyanonickelate complexes ofα-,β- andγ-picoline

Copper(II) dipicoline tetracyanonickelate complexes, CuL₂Ni(CN)₄ (L=,- or-picoline), have been prepared for the first time and their infrared and Raman spectra are reported. Their structure consists of polymeric layers of {Cu-Ni(CN)₄} with picoline molecules bound directly to the copper. It is proposed that the Cu-NC bonds are in two nonequivalent pairs in trans positions. Low temperature (83K) IR spectra have also been recorded and it is noted that the Ni(CN)₄ group frequencies increase with decreasing temperature while the picoline frequencies are insensitive to temperature.