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Concept

Sigma bond

Related publications (25)

Excited State-Specific CASSCF Theory for the Torsion of Ethylene

Sandra Saade

State-specific complete active space self-consistent field (SS-CASSCF) theory has emerged as a promising route to accurately predict electronically excited energy surfaces away from molecular equilibria. However, its accuracy and practicality for chemical ...

Amer Chemical Soc2024

Heterometallic uranium/molybdenum nitride synthesis via partial N-atom transfer

Rosario Scopelliti, Marinella Mazzanti, Luciano Barluzzi, Nadir Jori

The reaction of a terminal Mo(II) nitride with a U(III) complex yields an heterodimetallic U-Mo nitride which is the first example of a transition metal-capped uranium nitride. The nitride is triply bonded to U(V) and singly bonded to Mo(0) and supports a ...

Royal Society of Chemistry2022

Helical electronic transitions of spiroconjugated molecules

Anne-Clémence Corminboeuf, Marc Hamilton Folkmann Garner

The two pi-systems of allene can combine into helical molecular orbitals (MOs), yet the helicity is lost in the pi-pi* transitions due to excited state mixing. In spiroconjugated molecules the relative orientation of the two pi-systems is different and con ...

Royal Society of Chemistry2021

Diamine Synthesis via the Nitrogen-Directed Azidation of sigma- and pi-C-C Bonds

Jérôme Waser, Mingming Wang

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. ...

2021

Hydrogen Bonding of Ammonia with (H,OH)-Si(001) Revealed by Experimental and Ab Initio Photoelectron Spectroscopy

Alfredo Pasquarello, Oleg Yazyev

Combining experimental and ab initio core-level photoelectron spectroscopy (periodic DFT and quantum chemistry calculations), we elucidated how ammonia molecules bond to the hydroxyls of the (H,OH)-Si(001) model surface at a temperature of 130 K. Indeed, t ...

AMER CHEMICAL SOC2020

Ultrafast Photoelectron and Optical Spectroscopies of Photoinduced Processes in Molecular Systems in Solution

Luca Longetti

Investigating molecular excitations with femtosecond time resolution is of pivotal importance to understand the out-of-equilibrium processes taking place in molecular systems upon light absorption. The photochemistry of solvated species is heavily determin ...

EPFL2020

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

Small Molecule Activation by Multimetallic Uranium Complexes

Marta Falcone

The development of new processes for the selective and sustainable transformation of abundant small molecules constitutes one of the major research areas in inorganic and organometallic chemistry. These molecules as CO2, CO, N2 and H2 are abundant reservoi ...

EPFL2019

Interplay of H-Bonds with Aromatics in Isolated Complexes Identifies Isomeric Carbohydrates

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev, Ruslan Yamaletdinov

The tremendous isomeric diversity of carbohydrates enables a wide range of their biological functions but makes the identification and study of these molecules difficult. We investigated the ability of intermolecular interactions to communicate structural ...

Wiley-VCH Verlag GmbH2019

X-ray absorption linear dichroism at the Ti K edge of anatase TiO2 single crystals

Majed Chergui, Giulia Fulvia Mancini, Oliviero Cannelli, Thomas Charles Henry Rossi, Dominik Kinschel, Camila Bacellar Cases Da Silveira, Jérémy Raymond Jean Maurice Rouxel

Anatase TiO2 (a-TiO2) exhibits a strong x-ray absorption linear dichroism in the pre-edge, the XANES and the EXAFS at the titanium K edge. In the pre-edge region, the behavior of the A1-A3 and B peaks originating from the 1s - 3d transitions is due to the ...

2019

Are pi-pi Interactions in Ionic Liquids Related to Conductivities?

Paul Joseph Dyson, Rosario Scopelliti, Farzaneh Fadaei Tirani, Zhaofu Fei, Zhangjun Huang

A series of functionalised imidazolium halide salts with substituents able to form pi-bonds have been prepared and characterised. Subsequent reaction of these imidazolium halides with Ag[C(CN)(3)] affords imidazolium-based ionic liquids (ILs), some of whic ...

WILEY-V C H VERLAG GMBH2018

Equilibrium and Out-of-Equilibrium Adherence of Hydrogels against Polymer Brushes

Jennifer Mary Adrienne Alice Macron

At low pH, underwater adherence between poly(N,N-dimethylacrylamide) hydrogels and poly(acrylic acid) brushes is due to the formation of multiple hydrogen bonds. The effect of the key parameters controlling the formation of these interactions (contact time ...

American Chemical Society2018

Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering

Yixing Chen, Sylvie Roke, Halil Ibrahim Okur, Nathan Dupertuis

The temperature dependence of the femtosecond elastic second harmonic scattering (fs-ESHS) response of bulk light and heavy water and their electrolyte solutions is presented. We observe clear temperature dependent changes in the hydrogen (H)-bond network ...

2018

Fe N-Heterocyclic Carbene Complexes as Promising Photosensitizers

Yizhu Liu

The photophysics and photochemistry of transition metal complexes (TMCs) has long been a hot field of interdisciplinary research. Rich metal-based redox processes, together with a high variety in electronic configurations and excited-state dynamics, have r ...

American Chemical Society2016

Switchable [3+2] and [4+2] Heteroannulation of Primary Propargylamines with Isonitriles to Imidazoles and 1,6-Dihydropyrimidines: Catalyst Loading Enabled Reaction Divergence

Jieping Zhu, Qian Wang, Shuo Tong

Isonitrile 1 due to its carbene-like reactivity serves generally as a one-carbon synthon in a diverse set of organic transformations. We report in this article that the isocyano group can also act as a polarized triple bond to undergo, as a two-atom syntho ...

Wiley-Blackwell2016

Facile CO Cleavage by a Multimetallic CsU2 Nitride Complex

Rosario Scopelliti, Marinella Mazzanti, Marta Falcone

Uranium nitrides are important materials with potential for application as fuels for nuclear power generation, and as highly active catalysts. Molecular nitride compounds could provide important insight into the nature of the uranium–nitride bond, but curr ...

Wiley-VCH Verlag GmbH2016

Highly Enantioselective Rhodium(I)-Catalyzed Activation of Enantiotopic Cyclobutanone C-C Bonds

Nicolai Cramer, Laetitia Marie Mélanie Souillart

The selective functionalization of carbon-carbon sigma bonds is a synthetic strategy that offers uncommon retrosynthetic disconnections. Despite progress in CC activation and its great importance, the development of asymmetric reactions lags behind. Rhodiu ...

Wiley-VCH Verlag GmbH2014

How Strong Is Hydrogen Bonding in Ionic Liquids? Combined X-ray Crystallographic, Infrared/Raman Spectroscopic, and Density Functional Theory Study

Paul Joseph Dyson, Rosario Scopelliti, Gabor Laurenczy, Zhaofu Fei, Ning Yan, Emilia Paunescu

Hydrogen bonding in ionic liquids based on the 1-(2'-hydroxylethyl)-3-methylimidazolium cation (C(2)OHmim) and various anions (A) of differing H-bond acceptor strength, viz. hexafluorophosphate PF6, tetrafluoroborate BF4, bis-(trifluoro ...

American Chemical Society2013

Investigation of liquid LBE embrittlement effects on irradiated ferritic/martensitic steels by slow-strain-rate tensile tests

Nadine Baluc, Yong Dai

In the present work, LBE (lead-bismuth eutectic) embrittlement effects on ferritic/martensitic (FM) steels have been studied by conducting slow-strain-rate tensile (SSRT) testing on T91 and F82H steels either in Ar or in liquid LBE after irradiation to dos ...

Elsevier Science Bv2012

How do electron localization functions describe p-electron delocalization?

Anne-Clémence Corminboeuf

Scalar fields provide an intuitive picture of chemical bonding. In particular, the electron localization function (ELF) has proven to be highly valuable in interpreting a broad range of bonding patterns. The discrimination between enhanced or reduced elect ...

Royal Society of Chemistry2011