Concept

Valence (chimie)

Publications associées (85)

Why choosing the right partner is important: stabilization of ternary Cs(y)GUA(x)FA((1-y-x))PbI(3)perovskites

Ursula Röthlisberger, Marko Mladenovic, Ariadni Boziki

Lead halide perovskites with mixtures of monovalent cations have attracted wide attention due to the possibility of preferentially stabilizing the perovskite phase with respect to photovoltaically less suitable competing phases. Here, we present a theoreti ...

ROYAL SOC CHEMISTRY2020

Energetics and cathode voltages of LiMPO4 olivines (M = Fe, Mn) from extended Hubbard functionals

Nicola Marzari, Matteo Cococcioni

Transition-metal compounds pose serious challenges to first-principles calculations based on density functional theory (DFT), due to the inability of most approximate exchange-correlation functionals to capture the localization of valence electrons on thei ...

AMER PHYSICAL SOC2019

To bend or not to bend, the dilemma of multiple bonds

Michele Pizzochero

Beyond the second row of the periodic table, the nature of the multiple bonds between the elements of the main groups remains yet elusive, and "non-classical" bonding schemes are often invoked for their description. Here, focusing on group 14, we have perf ...

ROYAL SOC CHEMISTRY2019

Extrinsic Defects in Amorphous Oxides: Hydrogen, Carbon, and Nitrogen Impurities in Alumina

Alfredo Pasquarello, Francesco Ambrosio, Zhendong Guo

We present a procedure for addressing extrinsic defects in amorphous oxides, in which the most stable defect configurations are identified through ab initio molecular dynamics in various charge states and studied through hybrid functional calculations. The ...

2019

Kondo lattice excitation observed using resonant inelastic x-ray scattering at the YbM5 edge

Marco Grioni, Thorsten Schmitt, Marco Guarise

We present a study of the resonant inelastic scattering response of YbInCu4 excited at the tender YbM5 x-ray edge. In the high-temperature, paramagnetic phase, we observe a multiplet structure which can be understood at an ionic level. Upon cooling through ...

AMER PHYSICAL SOC2018

Ozone and chlorine reactions with dissolved organic matter - Assessment of oxidant-reactive moieties by optical measurements and the electron donating capacities

Urs von Gunten

Oxidation processes are impacted by the type, concentration and reactivity of the dissolved organic matter (DOM). In this study, the reactions between various types of DOM (Suwannee River fulvic acid (SRFA), Nordic Reservoir NOM (NNOM) and Pony Lake fulvic ...

2018

Noncovalent Molecular Electronics

Molecular electronics covers several distinctly different conducting architectures, including organic semiconductors and single-molecule junctions. The noncovalent interactions, abundant in the former, are also often found in the latter, i.e., the dimer ju ...

2018

Two analytical approaches quantifying the electron donating capacities of dissolved organic matter to monitor its oxidation during chlorination and ozonation

Urs von Gunten

Electron-donating activated aromatic moieties, including phenols, in dissolved organic matter (DOM) partially control its reactivity with the chemical oxidants ozone and chlorine. This comparative study introduces two sensitive analytical systems to direct ...

2018

Mixed cation perovskite solid state solar cell and fabrication thereof

Michael Graetzel, Shaik Mohammed Zakeeruddin, Wolfgang Richard Tress, Michael Saliba, Konrad Domanski, Jiyoun Seo, Taisuke Matsui

A perovskite material including an organic-inorganic perovskite structure of formula (I), AnMX3 (I), n being the number of cation A and an integer >4, A being a monovalent cation selected from inorganic cations Ai and/or from organic cations Ao, M being a ...

2018

Orientational ordering of water in extended hydration shells of cations is ion-specific and is correlated directly with viscosity and hydration free energy

Sylvie Roke, Yixing Chen, Halil Ibrahim Okur, Chung-Wen Liang

Specific ion effects in aqueous solutions are investigated at the molecular, nanoscopic and macroscopic levels. Femtosecond elastic second harmonic scattering (fs-ESHS) is used here to assess the chemical effects of ions on molecular and nanoscopic length ...

2017

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