Search results for "phosphides"

showing 3 items of 3 documents

The Taming of Redox‐Labile Phosphidotitanocene Cations

2019

International audience; Tame d0 phosphidotitanocene cations stabilized with a pendant tertiary phosphane arm are reported. These compounds were obtained by one-electron oxidation of d1 precursors with [Cp2Fe][BPh4]. The electronic structure of these compounds was studied experimentally (EPR, UV/Vis, and NMR spectroscopy, X-ray diffraction analysis) and through DFT calculations. The theoretical analysis of the bonding situation by using the electron localization function (ELF) shows the presence of π-interactions between the phosphido ligand and Ti in the d0 complexes, whereas dπ–pπ repulsion prevents such interactions in the d1 complexes. In addition, CH–π interactions were observed in seve…

010402 general chemistry01 natural sciencesRedoxTransition metal phosphidesCatalysisFrustrated Lewis pairlaw.inventionchemistry.chemical_compoundFrustrated Lewis Pair (FLP)[CHIM.ANAL]Chemical Sciences/Analytical chemistrylaw[CHIM.COOR]Chemical Sciences/Coordination chemistryPhosphorus LigandsElectron paramagnetic resonanceDiphenylacetyleneComputingMilieux_MISCELLANEOUSTitanium[CHIM.ORGA]Chemical Sciences/Organic chemistry010405 organic chemistryLigandOrganic Chemistry[CHIM.MATE]Chemical Sciences/Material chemistryGeneral ChemistryNuclear magnetic resonance spectroscopyElectron localization function0104 chemical sciencesHomolysis[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistryDensity Functional Theory (DFT)Crystallographychemistry[CHIM.CHEM]Chemical Sciences/CheminformaticsChemistry – A European Journal
researchProduct

Positron lifetime measurements on neutron‐irradiated InP crystals

1996

Neutron‐irradiated InP single crystals have been investigated by positron‐lifetime measurements. The samples were irradiated with thermal neutrons at different fluences yielding concentrations for Sn‐transmuted atoms between 2×1015 and 2×1018 cm−3. The lifetime spectra have been analyzed into one exponential decay component. The mean lifetimes show a monotonous increase with the irradiation dose from 246 to 282 ps. The increase in the lifetime has been associated to a defect containing an Indium vacancy. Thermal annealing at 550 °C reduces the lifetime until values closed to those obtained for the as‐grown and conventionally doped InP crystals. navarrof@evalvx.ific.uv.es ; Jose.Ferrero@uv.es

Materials sciencePhysics::Instrumentation and DetectorsPhysics::Medical PhysicsAnalytical chemistryGeneral Physics and Astronomychemistry.chemical_elementDefect StructureMonocrystalsSpectral lineCondensed Matter::Materials Science:FÍSICA [UNESCO]Vacancy defectNeutronIrradiationIndium Phosphides ; Radiation Effects ; Thermal Neutrons ; Monocrystals ; Positron Probes ; Lifetime ; Defect StructureExponential decayPositron ProbesDopingRadiochemistryUNESCO::FÍSICANeutron temperatureRadiation EffectschemistryIndium PhosphidesThermal NeutronsLifetimeIndiumJournal of Applied Physics
researchProduct

Insertion Reactions of Neutral Phosphidozirconocene Complexes as a Convenient Entry into Frustrated Lewis Pair Territory

2016

International audience; Neutral phosphidozirconocene complexes [Cp2Zr(PR2)Me] (Cp=cyclopentadienyl; 1a: R=cyclohexyl (Cy); 1b: R=mesityl (Mes); 1c: R=tBu) undergo insertion into the Zr-P bond by non-enolisable carbonyl building blocks (O=CRR), such as benzophenone, aldehydes, paraformaldehyde or CO2, to give [Cp2Zr(OCRRPR2)Me] (3-7). Depending on the steric bulk around P, complexes 3-7 react with B(C6F5)(3) to give O-bridged cationic zirconocene dimers that display typical frustrated Lewis pair (FLP)/ambiphilic ligand behaviour. Thus, the reaction of {[Cp2Zr(-OCHPhPCy2)][MeB(C6F5)(3)]}(2) (10a) with chalcone results in 1,4 addition of the Zr+/P FLP, whereas the reaction of {[Cp2Zr(-OCHFcPCy…

Steric effectsChalconeStereochemistryzirconiumc-h activation010402 general chemistry01 natural sciencesMedicinal chemistry[ CHIM ] Chemical SciencesCatalysisFrustrated Lewis pairinsertionchemistry.chemical_compoundCyclopentadienyl complexx-ray structuresphosphinidene complexesBenzophenone[CHIM]Chemical SciencesParaformaldehydezr-p bondzirconocene-phosphido complexesmolecular-structure010405 organic chemistryLigandphosphidesOrganic ChemistryCationic polymerizationcrystal-structureGeneral Chemistry0104 chemical sciencesfunctionalized ligandsbis(trimethylsilyl)phosphido complexeschemistryfrustrated Lewis pairsphosphinoaryloxide complexesambiphilic ligands
researchProduct