Five-coordinated iron(II)

Theoretical study of a five-coordinated silica polymorph

Theoretical calculations are performed to study transformations in silica as a function of nonhydrostatic stress. Molecular-dynamics calculations reveal a crystalline-to-crystalline transition from a-quartz to a phase with five-coordinated silicon (Si) at high pressure in the presence of deviatoric stress. The phase, which appears for specific orientations of the stress tensor relative to the c...

Spectroscopic properties of five-coordinated Co2+ in phosphates.

Co3(PO4)2, SrCo2(PO4)2, Co2P2O7, BaCoP2O7 and SrCoP2O7 present different geometries of five-coordinated Co(2+) (([5])Co(2+)) sites, coexisting with ([6])Co(2+) in Co3(PO4)2 and Co2P2O7, and ([4])Co(2+) in SrCo2(PO4)2. ([5])Co K-edge XANES spectra show that the intensity of the pre-edge and main-edge is intermediate between those of ([6])- and ([4])Co. Diffuse reflectance spectra show the contri...

Luminescence of five-coordinated nickel(ii) complexes with substituted-8-hydroxyquinolines and macrocyclic ligands.

A series of heteroleptic quinolinolate pentacoordinated nickel(ii) complexes, [Ni(mcN(3))(R(1),R(2),R(3)-8-hq)](PF(6)), were synthesized and characterized by spectroscopic methods. Single-crystal X-ray diffraction studies for [(Me(3)-mcN(3))Ni(N,O-2-CN-8-hq)][PF(6)] (6a), [(Me(4)-mcN(3))Ni(N,O-8-hq)][PF(6)] (2b) and [(Me(4)-mcN(3))Ni(N,O-5,7-I(2)-8-hq)][PF(6)] (5b) indicate that these complexes...

Coordinated and Joint Ordering Policies for Two Commodity Inventory System

Synthesis and Characterization of Nanocrystalline Magnetic Pigment via Coordinated Precursors

Nanocrystalline cobalt ferrite as a magnetic black pigment was synthesized via coordinated precursors with a significant decrease of the synthesis temperature using citric acid as a coordinating agent. The structure and properties of the cobalt ferrite powder were characterized by X-ray diffraction (XRD), colorimetric analysis (L*a*b* color parameters), diffuse reflectance spectroscopy and vibr...