Publications associées à Uranyl complexes formed with a para-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies

Palladium-based supramolecular assemblies: from complex structures to water-soluble anion-receptors

The combination of palladium salts and bipyridyl ligands can lead to the formation of a large variety of coordination complexes, with different shapes and sizes, displaying a very versatile host-guest chemistry. Increasing their structural complexity remai ...

EPFL2024

Surfactant-based enrichment of rare earth elements from NdFeB magnet e-waste: Optimisation of cloud formation and rare earths extraction

Christian Ludwig, Rudolf Paul Wilhelm Jozef Struis, Mohamed Tarik, Ajay Bhagwan Patil

Appropriate waste and resource management are essential for a sustainable circular economy with reduced environmental impact. With critical resources, e-waste may serve as indirect raw material. For example, with NdFeB permanent magnets, Neodymium (Nd) and ...

2023

Stabilizing Unusual Oxidation States of Lanthanides in Molecular Complexes: Synthesis, Properties, and Reactivity

Aurélien René Willauer

The chemistry of divalent lanthanides has generated increasing interest in the past years due to their redox properties and unique reaction pathways. Notably, molecular complexes of low-valent lanthanides have been shown to be suitable one-electron reducta ...

EPFL2022

Colorimetry of Luminescent Lanthanide Complexes

Anne-Sophie Chauvin, Julien Alexandre Andres

Europium, terbium, dysprosium, and samarium are the main trivalent lanthanide ions emitting in the visible spectrum. In this work, the potential of these ions for colorimetric applications and colour reproduction was studied. The conversion of spectral dat ...

2020

Sensing the Spin of an Individual Ce Adatom

Wolf-Dieter Schneider, Markus Ternes

The magnetic moment of rare earth elements originates from electrons in the partially filled 4f orbitals. Accessing this moment electrically by scanning tunneling spectroscopy is hampered by shielding of outerlying orbitals. Here, we show that we can detec ...

AMER PHYSICAL SOC2020

Structure and small molecule activation reactivity of a metallasilsesquioxane of divalent ytterbium

Rosario Scopelliti, Marinella Mazzanti, Aurélien René Willauer

The first metallasilsesquioxane of a divalent lanthanide, Yb{Cy7Si7O11(OSiMe3)}(THF),1, was synthesized and structurally characterized. The Cy7Si7O11(OSiMe3)(2-)ligands in1bind two Yb(ii) ions in a bridging mode. The dinuclear complex effects the two- ...

Royal Society of Chemistry2020

Structure-Property Relationships of Microphase-Separated Metallosupramolecular Polymers

Emad Oveisi, Stephen Schrettl

The structural, thermomechanical, and viscoelastic properties of metallosupramolecular polymers (MSPs) can be controlled through the choice of the multiligand monomer and the nature of the metal salt from which these materials are assembled. This versatili ...

American Chemical Society2020

Accessing the plus IV Oxidation State in Molecular Complexes of Praseodymium

Marinella Mazzanti, Ivica Zivkovic, Farzaneh Fadaei Tirani, Aurélien René Willauer

Out of the 14 lanthanide (Ln) ions, molecular complexes of Ln(IV) were known only for cerium and more recently terbium. Here we demonstrate that the +IV oxidation state is also accessible for the large praseodymium (Pr) cation. The oxidation of the tetraki ...

2020

Synthesis, reactivity, and environmental relevance of uranyl(V) complexes

Radmila Faizova

Knowledge of fundamental chemical properties of all environmentally relevant uranium species is essential to understand environmental uranium mobility and develop novel remediation strate-gies. A myriad of uranium(VI) and uranium(IV) compounds has been stu ...

EPFL2020

Measuring the Intra-Atomic Exchange Energy in Rare-Earth Adatoms

Harald Brune, François Patthey, Stefano Rusponi, Marina Pivetta

We present the first experimental determination of the intra-atomic exchange energy between the inner 4f and the outer 6s5d shells in rare-earth elements. Inelastic electron tunneling spectroscopy on individual rare-earth atoms adsorbed on metal-supported ...

American Physical Society2020

Activation of small molecules promoted by multimetallic complexes supported by redox active ligands

Davide Toniolo

The activation of small molecule is a topic of high current interest. A variety of homogeneous end heterogeneous catalysts have been studied to be able to promote chemical transformation of industrial relevance under mild condition and therefore decrease t ...

EPFL2020

Molecular Complex of Tb in the +4 Oxidation State

Rosario Scopelliti, Marinella Mazzanti, Ivica Zivkovic

Lanthanides (Ln) usually occur in the +3, or more recently the +2, oxidation states. The only example of an isolated molecular Ln(4+) so far remains Ce4+. Here we show that the +4 oxidation state is also accessible in a molecular compound of terbium as dem ...

2019

A Study on the Characteristics of Cu-Mn-Dy Alloy Resistive Thin Films

Ho-Yun Lee

Cu-Mn-Dy resistive thin films were prepared on glass and Al2O3 substrates, which was achieved by co-sputtering the Cu-Mn alloy and dysprosium targets. The effects of the addition of dysprosium on the electrical properties and microstructures of annealed Cu ...

2019

The effect of iron binding on uranyl(V) stability

Rosario Scopelliti, Marinella Mazzanti, Radmila Faizova

Here we report the effect of UO2+⋯Fe2+ cation–cation interactions on the redox properties of uranyl(V) complexes and on their stability with respect to proton induced disproportionation. The tripodal heptadentate Schiff base trensal3− ligand allowed the sy ...

2018

Lanthanide mechanoluminescence

Jean-Claude Bünzli

Mechanoluminescence (ML) is the emission of light consecutive to a mechanical force or stress imposed to a crystalline material. Many inorganic and organic compounds present this phenomenon that is known for over 400 years. Lanthanide and uranyl salts were ...

Elsevier Science Bv2018

Features of proteolytic properties of tetraphenylporphyrin complex with lanthanide group metals

Demetallation of metalloporphyrin molecules is one of the essential degradation reactions in photosynthesis. The effect of metalloporphyrin nature on removal of central metals from tetraphenylporphyrin complexes based on lanthanide group metals (Dy, Er, Lu ...

2018

Reduction of a Cerium(III) Siloxide Complex To Afford a Quadruple-Decker Arene-Bridged Cerium(II) Sandwich

Rosario Scopelliti, Marinella Mazzanti, Rory Patrick Kelly

Organometallic multi-decker sandwich complexes containing f-elements remain rare, despite their attractive magnetic and electronic properties. The reduction of the Ce-III siloxide complex, [KCeL4] (1; L = OSi(OtBu)(3)), with excess potassium in a THF/tolue ...

Wiley-VCH Verlag GmbH2017

4 f occupancy and magnetism of rare-earth atoms adsorbed on metal substrates

Harald Brune, Pietro Gambardella, Stefano Rusponi, Sebastian Stepanow, Fabio Donati, Aparajita Singha, Jan Gui-Hyon Dreiser, Christian Wäckerlin, Romana Baltic

We report x-ray absorption spectroscopy and x-ray magnetic circular dichroism measurements as well as multiplet calculations for Dy, Ho, Er, and Tm atoms adsorbed on Pt(111), Cu(111), Ag(100), and Ag(111). In the gas phase, all four elements are divalent a ...

Amer Physical Soc2017

Magnetic properties of surface-adsorbed single rare earth atoms, molecules, and atomic scale clusters

Aparajita Singha

This thesis presents combined experimental and theoretical investigations of nanoscale, surface-supported magnets based on rare earths (RE) to understand and control the magnetic properties down to the scale of single atoms. We present the effects of adato ...

EPFL2017

Synthesis of molecular complexes for small molecule activation

Julie Renée Michelle Andrez

The redox chemistry of f-elements is drawing the attention of inorganic chemists due to their unusual reaction pathways. Notably low-valent f-element complexes have been shown to be able to activate small molecules such as CO2 and N2 in mild conditions. Co ...

EPFL2016