Search results for "coordination"
showing 10 items of 1282 documents
Bidirectional Chemo-Switching of Spin State in a Microporous Framework
2009
The ins and outs of spin: Using the microporous coordination polymer {Fe(pz)[Pt(CN)(4)]} (1, pz=pyrazine), incorporating spin-crossover subunits, two-directional magnetic chemo-switching is achieved at room temperature. In situ magnetic measurements following guest vapor injection show that most guest molecules transform 1 from the low-spin (LS) state to the high-spin (HS) state, whereas CS(2) uniquely causes the reverse HS-to-LS transition.
Polyamines : études et applications
2008
International audience
Synthèse et étude physico-chimique de ligands macrocycliques, macrobicycliques et macrotricycliques dérivés du 5,12-dioxocyclame
2002
The synthesis and the physico-chemical studies of macropolycyclic ligands based on 5,12-dioxocyclam L1 are presented. The first part of this dissertation presents the structural and physico-chemical properties of L1 and its N-substituted derivatives L2 and L3. A potentiometric study reveald a cooperative protonation of the two macrocyclic ligands L1 and L2 whereas the study of the macrotricycle L3 in a methanol-water mixture revealed a sequential cooperative diprotonation of the four tertiary amines. The square planar nickel and copper complexes were synthesized and characterized using infrared, UV-vis and ESR spectgroscopy. The spectroscopic studies showed the presence of intermolecular hy…
Copper( ii ) complexes with phosphorylated 1,10-phenanthrolines: from molecules to infinite supramolecular arrays
2016
International audience; The reaction of phosphorylated 1,10-phenanthrolines 3-Pphen, 3,8-Pphen and 4,7-Pphen (3-Pphen = 3-diethoxyphosphorylphenanthroline, 3,8-Pphen = 3,8-bis(diethoxyphosphoryl) phenanthroline, 4,7-Pphen = 4,7-bis(diethoxyphosphoryl) phenanthroline) and hydrated copper(II) nitrate in a 1 : 1 ratio leads to the formation of supramolecular architectures. In the 1D coordination polymer [Cu(3-Pphen)(NO3)(2)](n) (2) the copper atom is coordinated to only one phenanthroline ligand and the coordination sphere is completed by two oxygen atoms of nitrate anions and the oxygen atom of the phosphoryl group from the neighbouring phenanthroline ligand. Complex Cu(3,8-Pphen)(NO3)(2) (3)…
Naja, normal und normal. Zur Syntax, Semantik und Pragmatik der x-und-x-Konstruktion im Deutschen
2012
This article deals with the syntax, semantics and pragmatics of the x und x (‘x and x’) construction in German, cf. A: Schade, dass die [Schabracken] so teuer sind! B: Naja, teuer und teuer, wenn die Qualitat stimmt, dann finde ich den Preis okay. (A: ‘What a pity that the horsetrappers are so expensive!’ B: ‘Well, expensive and expensive, if the quality is good, the price is fine with me.’). The specific discourse function of this construction is to negotiate the situational meaning of a previously used lexical item. Typologically, it has been claimed that the pattern is language-specific for Scandinavian. The paper challenges this assumption, providing empirical evidence from a questionna…
The Hold-Up Problem in Agricultural Contracts. A Study of Contractual Correlations Between Polish Groups of Agricultural Producers and First Recipien…
2018
Problem pułapki przed- i post-kontraktowej ma miejsce, gdy partnerzy cechują się oportunizmem, kontrakt jest niekompletny i występuje konieczność dokonania inwestycji zarówno o charakterze specyficznym, jak i ogólnego użytku. Na problem pułapki kontraktowej mogą być narażeni producenci rolni choćby ze względu na słabszą pozycję rynkową czy też niski poziom zintegrowania horyzontalnego. W artykule wyznaczono dwa cele. Pierwszy stanowi identyfikację umów rolnych, z których realizacją wiązało się dokonanie inwestycji w aktywa trwałe (problem pułapki post-kontraktowej). Drugim zaś jest rozpoznanie grup producentów rolnych, które według własnej opinii były w toku swej działalności narażone na wy…
Current Accounts and Coordination of Wage Bargaining
2018
This study provides novel evidence on the impact of labor market institutions on current account dynamics. Our results suggest that a high degree of coordination of wage bargaining has a positive effect on the current account balance over the long run. This result is not driven entirely by wage moderation induced by centralized wage setting. We also provide robust evidence that a high degree of coordination of wage bargaining is associated with a slower current account adjustment toward its long-run equilibrium. This result seems theoretically plausible; the aggregate shocks in the exporting sector are largely driven by idiosyncratic shocks and the presence of idiosyncratic shocks increases…
Essays on current account imbalances
2017
Global current account imbalances and intra-euro area imbalances have been at the forefront of academic and policy debates for the last ten years. This thesis examines the determinants of current account balances and external adjustment. It consists of an introduction and four empirical studies. This thesis highlights the importance of institutional factors such as differences in national cultures and cross-country differences in the coordination of wage bargaining on external balances. The first study investigates the effects of deep determinants on current account balances. The point estimates are economically and statistically significant, suggesting that countries populated by Roman Cat…
Interplay between spin transition and gas sorption in compartmentalized coordination polymers
2019
El trabajo descrito en esta tesis se enmarca dentro de los polímeros de coordinación compartimentalizados. Los polímeros de coordinación son materiales híbridos orgánicos-inorgánicos formados por un metal rodeado por unos ligandos orgánicos unidos mediante enlace de coordinación y se pueden obtener estructuras que se extienden en una, dos o tres direcciones del espacio. Las infinitas posibilidades que existen debido a la gran variedad de metales disponibles y especialmente, a la posibilidad de sintetizar múltiples ligandos orgánicos permite diseñar químicamente materiales con propiedades “a la carta”, además de la posibilidad de presentar multifuncionalidad, esto es, la combinación de diver…
Inverted molecular cups: 1-D and 2-D Ag(I) coordination polymers from resorcinarene bis-thiacrowns
2016
Resorcinarene bis-thiacrown hosts 1–3 were prepared and crystallized with silver trifluoroacetate yielding one and two dimensional Ag coordination polymers. The complexation of silver in exo-cavity fashion folds the thiacrown bridges inwards transforming the resorcinarene hosts into inverted molecular cups. The silver cations were coordinated to the resorcinarene ligands and trifluoroacetate anions, which act as monodentate or bidendate bridging ligands between the metal ions. Argentophilic Ag···Ag (2.93–3.38 Å) interactions supported by two bridging carboxylate anions were found in two of the structures, whereas longer Ag···Ag distances were observed if only one anion connected the silver …