The Chemical Bond in Polyphosphides: Crystal Structures, the Electron Localization Function, and New View of Aromaticity in P42- and P5-.

ChemInform ◽  
2006 ◽  
Vol 37 (8) ◽  
Author(s):  
Florian Kraus ◽  
Nikolaus Korber
Keyword(s):  
Crystal Structures ◽  
Chemical Bond ◽  
Electron Localization Function ◽  
Electron Localization ◽  
Localization Function ◽  
New View

scholarly journals The half Heusler system Ti1+xFe1.33−xSb–TiCoSb with Sb/Sn substitution: phase relations, crystal structures and thermoelectric properties

2018 ◽  
Vol 47 (3) ◽  
pp. 879-897 ◽  
Author(s):  
A. Tavassoli ◽  
A. Grytsiv ◽  
G. Rogl ◽  
V. V. Romaka ◽  
H. Michor ◽  
...  
Keyword(s):  
Phase Equilibria ◽  
Crystal Structures ◽  
Thermoelectric Properties ◽  
Phase Relations ◽  
Electron Localization Function ◽  
Electron Localization ◽  
Heusler Phase ◽  
Localization Function ◽  
Sn Substitution

Phase equilibria for Heusler Phase Ti1+xFe1.33−xSb at 800 °C and calculated isosurfaces (ϒ = 0.42) of the electron localization function in TiFe1.25Sb.

The Electron Localization Function in Excited States: The Case of the Ultra-Fast Proton Transfer of the Salicylidene Methylamine

2019 ◽  
Author(s):  
Andrea Echeverri ◽  
Tatiana Gómez ◽  
Patricio Fuentealba ◽  
Boris Maulen ◽  
Carlos Cardenas
Keyword(s):  
Excited State ◽  
Proton Transfer ◽  
Chemical Bond ◽  
Excited States ◽  
Ground State ◽  
Topological Analysis ◽  
Photochemical Reactions ◽  
Electron Localization Function ◽  
Electron Localization ◽  
Localization Function

The physical characterization of the chemical bond in the ground state has been a central theme to theoretical chemistry. Among many techniques, quantum chemical topology (QCT) has emerged as a robust technique to understand the features of the chemical bond and electron organization within molecules. One consolidate tool within QCT is the topological analysis of the electron localization function (ELF). Most research on ELF and chemical bond has focused either on singlet ground states or the first excited triplet. However, most photochemical reactions and photophysical processes occur in excited states with the same spin-symmetry as the ground state. In this work, we develop a proposal on how to compute the ELF in excited states of any symmetry within linear-response time-dependent density functional theory. Then, we study the evolution of the chemical bonds in the ground and excited state intramolecular proton transfer (ESIPT) of a prototypal Schiff Base (the salicylidene methylamine, Scheme 1). We found that the topological analysis of the ELF along reaction paths explain the presence of a barrier for the proton transfer in the ground state and the absence of it in the excited state. Briefly, in the ground state, the cleavage of the O-H bond results in a structure with high electrostatic potential energy due to an excess of electron lone-pairs (3) in the Oxygen atom, which explains the barrier. In the excited state, the electronic transition promotes an enhancement of the basicity of Nitrogen by allocating three nonbonding electrons in the basin of its lone-pair. This excess of electrons in the N exerts an electrostatic attraction of the proton, which we suggest as the primary driven-force of the barrierless reaction. Because in excited states the molecule can develop more vibrational kinetic energy than in the ground state, we perfumed an ab initio molecular dynamics of the proton transfer in the excited state and corroborate that our conclusions on the topology of the ELF do not change due to dynamic effects.

The Electron Localization Function in Excited States: The Case of the Ultra-Fast Proton Transfer of the Salicylidene Methylamine

2019 ◽  
Author(s):  
Andrea Echeverri ◽  
Tatiana Gómez ◽  
Patricio Fuentealba ◽  
Boris Maulen ◽  
Carlos Cardenas
Keyword(s):  
Excited State ◽  
Proton Transfer ◽  
Chemical Bond ◽  
Excited States ◽  
Ground State ◽  
Topological Analysis ◽  
Photochemical Reactions ◽  
Electron Localization Function ◽  
Electron Localization ◽  
Localization Function

The physical characterization of the chemical bond in the ground state has been a central theme to theoretical chemistry. Among many techniques, quantum chemical topology (QCT) has emerged as a robust technique to understand the features of the chemical bond and electron organization within molecules. One consolidate tool within QCT is the topological analysis of the electron localization function (ELF). Most research on ELF and chemical bond has focused either on singlet ground states or the first excited triplet. However, most photochemical reactions and photophysical processes occur in excited states with the same spin-symmetry as the ground state. In this work, we develop a proposal on how to compute the ELF in excited states of any symmetry within linear-response time-dependent density functional theory. Then, we study the evolution of the chemical bonds in the ground and excited state intramolecular proton transfer (ESIPT) of a prototypal Schiff Base (the salicylidene methylamine, Scheme 1). We found that the topological analysis of the ELF along reaction paths explain the presence of a barrier for the proton transfer in the ground state and the absence of it in the excited state. Briefly, in the ground state, the cleavage of the O-H bond results in a structure with high electrostatic potential energy due to an excess of electron lone-pairs (3) in the Oxygen atom, which explains the barrier. In the excited state, the electronic transition promotes an enhancement of the basicity of Nitrogen by allocating three nonbonding electrons in the basin of its lone-pair. This excess of electrons in the N exerts an electrostatic attraction of the proton, which we suggest as the primary driven-force of the barrierless reaction. Because in excited states the molecule can develop more vibrational kinetic energy than in the ground state, we perfumed an ab initio molecular dynamics of the proton transfer in the excited state and corroborate that our conclusions on the topology of the ELF do not change due to dynamic effects.

The nature of the chemical bond in di- and polynuclear metal cluster complexes as depicted by the analysis of the electron localization function

2005 ◽  
Vol 8 (9-10) ◽  
pp. 1400-1412 ◽  
Author(s):  
Juan Andrés ◽  
Slawomir Berski ◽  
Marta Feliz ◽  
Rosa Llusar ◽  
Fabricio Sensato ◽  
...  
Keyword(s):  
Chemical Bond ◽  
Metal Cluster ◽  
Electron Localization Function ◽  
Electron Localization ◽  
Cluster Complexes ◽  
Localization Function

scholarly journals On the Importance of Clar Structures of Polybenzenoid Hydrocarbons as Revealed by the π-Contribution to the Electron Localization Function

Symmetry ◽  
2010 ◽  
Vol 2 (3) ◽  
pp. 1653-1682 ◽  
Author(s):  
Jun Zhu ◽  
Christian Dahlstrand ◽  
Joshua R. Smith ◽  
Sébastien Villaume ◽  
Henrik Ottosson
Keyword(s):  
Electron Localization Function ◽  
Electron Localization ◽  
Localization Function ◽  
Clar Structures
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