Vibrational Study of Dipotassium Zinc Bis(Dihydrogendiphosphate) Dihydrate,K2ZN(H2P2O7)2·2H2O

Abstract

Infrared and Raman spectra of dipotassium zinc bis(dihydrogendiphosphate) dihydrate, K₂Zn(H₂P₂O₇)₂ .2H₂O have been collected and interpreted using factor group analysis. Noncoincidence of the Raman and infrared spectra bands confirms a centrosymmetric structure for K₂Zn(H₂P₂O₇)₂ .2H₂O previously investigated by X-ray structural study, as well as the joint appearance of ν_as POP and ν_s POP point to a bent POP configuration.     

Theoretical Study on Non-Linear Optics Properties of Polycyclic Aromatic Hydrocarbons and the Effect of Their Intercalation with Carbon Nanotubes

Results of a theoretical study devoted to comparing NLO (non-linear optics) responses of derivatives of tetracene, isochrysene, and pyrene are reported. The static hyperpolarizability β, the dipole moment μ, the HOMO and LUMO orbitals, and their energy gap were calculated using the CAM-B3LYP density functional combined with the cc-pVDZ basis set. The para-disubstituted NO₂-tetracene-N(CH₃)₂ has the highest NLO response, which is related to a large intramolecular charge transfer. Adding vinyl groups to the para-disubstituted NO₂-tetracene-N(CH₃)₂ results in an increase in the NLO responses. We further investigated the effect of the intercalation of various push–pull molecules inside an armchair single-walled carbon nanotube. The intercalation leads to increased NLO responses, something that depends critically on the position of the guest molecule and/or on functionalization of the nanotube by donor and attractor groups.     

Preparation and characterization of supported bimetallic gold–iron nanoparticles,and its potential for heterogeneous catalysis

Research on Chemical Intermediates - Bimetallic gold–iron catalysts supported on ZrO2 and TiO2 were prepared by under potential deposition. The characterization of the catalysts was performed...     

Chiral copper(II) bisoxazoline covalently anchored to silica and mesoporous MCM-41 as a heterogeneous catalyst for the enantioselective Friedel-Crafts hydroxyalkylation

Two solid catalysts in which a chiral copper(II) bisoxazoline has been covalently anchored on silica and MCM-41 have been prepared; the solids are enantioselective catalysts (up to 92% ee) for the Friedel-Crafts hydroxyalkylation of 1,3-dimethoxybenzene with 3,3,3-trifluoropyruvate.     

La Categorie desb-Espaces de de Wilde

We give a construction of a category which is stable for injective and countable inductive limits and for countable projective limits, and we prove the bornological DeWilde theorem.

     

Selective gas-phase hydrogenation of benzaldehyde in the presence of Ni-, Co- and Fe-doped BaCuO2 delafossites: effect of metal substituent on the production of benzyl alcohol

Research on Chemical Intermediates - Delafossite mixed metal oxides of the form BaCuO2 and BaCu1M1?xO2 (M?=?Ni, Fe and Co) were successfully synthesized following a sol–gel...     

Structural study of bonding in halogeno ruthenium complexes: Application to ruthenium nitrosyls

The halogeno nitrosyl ruthenium complexes are studied using their structural characteristics as basis. The structures of K₂RuNOX ₅ (X=Cl, Br, I) have been determined or redetermined. The study of the bond lengths Ru-Cl is, in a first part, placed in the general frame of the chlorocomplexes of ruthenium having and+ type ligands. The comparison points to a lengthening of the Ru-Cl_axial bond in [RuNOCl₅]^2–, which is opposite to the trans shortening effect up to now considered. A second part deals with the deformation of the octahedral coordination of the ruthenium atom. In [RuNOX ₅]^2–, the distance from the ruthenium to the equatorial plane varies with the position ofX in the spectrochemical series. The role of thed _xy orbital in the geometry of these ions is discussed.     

Influence of the macromolecular architecture on the self-assembly of amphiphilic copolymers based on poly(N,N-dimethylamino-2-ethyl methacrylate) and poly(epsilon-caprolactone)

The self-assembly of amphiphilic copolymers consisting of poly( N, N-dimethylamino-2-ethyl methacrylate) (PDMAEMA) and poly(-caprolactone) (PCL) segments arranged in graft and linear diblock architectures was investigated in this work by means of dynamic light scattering (DLS) in aqueous solution and by atomic force microscopy (AFM) on thin deposits. The solid-state deposits of the micelles were generated by a "freeze-drying" technique that preserves the initial micelle morphology in solution. A comparison between the morphological properties of graft copolymers with corresponding diblock copolymers was established to demonstrate the effect of the copolymer architecture on the micelle structure and organization.