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Perspective:Chemical Information Encoded in Electron Density

物理化学学报 2018年第6期34卷 567-580页

作者： contreras-GARCíA julia YANG Weitao UPMC Univ Paris 06 CNRSUMR 7616Laboratoire de Chimie Théorique Department of Chemistry Duke University

In this perspective,we review the chemical information encoded in electron density and other ingredients used in semilocal *** information is usually looked at from the functional point of view:the exchange density or the enhancement factor are discussed in terms of the reduced density ***,what parts of a molecule do these 3D functions represent? We look atthese quantities in real space,aiming to understand the electronic structure information they encode and provide an insight from the quantum chemical topology(QCT).Generalized gradient approximations(GGAs) provide information about the presence of chemical interactions,whereas meta-GGAs can differentiate between the different bonding *** merging these two techniques,we show new insight into the failures of semilocal functionals owing to three main errors:fractional charges,fractional spins,and non-covalent *** build on simple *** also analyze the delocalization error in hydrogen chains,showing the ability of QCT to reveal the delocalization error introduced by semilocal ***,we show how the analysis of localization can help understand the fractional spin error in alkali atoms,and how it can be used to correct ***,we show that the poor description of GGAs of isodesmic reactions in alkanes is due to 1,3-interactions.

关键词： DFT Semi-local functional Electron density Quantum chemical topology

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Understanding Chemical Reactivity in Extended Systems：Exploring Models of Chemical Softness in Carbon Nanotubes

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物理化学学报 2018年第6期34卷 631-638页

作者： CáRDENAS Carlos MUNOZ Macarena contreras julia AYERS Paul W. GóMEZ Tatiana FUENTEALBA Patricio Departamento de Flsica Facultad de Ciencias Universidad de Chile Casilla 653 Santiago Chile Centro para el Desarrollo de la Nanociencias y Nanotecnologia CEDENNA Avenida Ecuador 3493 Santiago Chile Nucleo de Matematicas Fisica y Estad

Chemical reactivity towards electron transfer is captured by the Fukui ***,this is not well defined when the system or its ions have degenerate or pseudo-degenerate ground *** such a case,the first-order chemical response is not independent of the perturbation and the correct response has to be computed using the mathematical formalism of perturbation theory for degenerate ***-degeneracy is ubiquitous in nanostructures with high symmetry and totally extended *** the size of these systems,using degenerate-state perturbation theory is impractical because it requires the calculation of many excited *** we present an alternative to compute the chemical response of extended systems using models of local softness in terms of the local density of *** local softness is approximately equal to the density of states at the Fermi ***,such approximation leaves out the contribution of inner *** order to include and weight the contribution of the states around the Fermi level,a model inspired by the long-range behavior of the local softness is *** wall capped carbon nanotubes(SWCCNT) illustrate the limitation of the frontier orbital theory in extended ***,we have used a C360 SWCCNT to test the proposed model and how it compares with available models based on the local density of ***,a simple Hü ckel approximation captures the main features of chemical response of these *** results suggest that density-of-states models of the softness along simple tight binding Hamiltonians could be used to explore the chemical reactivity of more complex system,such a surfaces and nanoparticles.

关键词： Local softness Fukui function Reactivity Carbon nanotubes Density of states

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X-ray Diffraction and Theoretical Calculation Supported Formation of Stoichiometric Diversity: Salicylic Acid: 3-Nitrobenzamide Cocrystals Discovered through Thermal Analysis

X-ray Diffraction and Theoretical Calculation Supported Form...

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2018年第十二届中国药物制剂大会

作者：周政政 Mónica Calatayud julia contreras-García Liang Li Henry H.Y.Tong Ying Zheng Department of Hygiene Inspection & Quarantine Science Guangdong Provincial Key Laboratory of Tropical Disease Research School of Public Health Southern Medical University Sorbonne Universite?s Laboratoire de Chimie The?orique UPMC Univ Paris 06 Department of Forensic Medicine Zhongshan School of Medicine Sun Yat-sen University School of Health Sciences Macao Polytechnic Institute State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Sciences University of Macau

＜正＞Purpose The purpose of this work was to discover new cocrystals with stoichiometric diversity by thermal methods and elucidate their formation mechanism through theoretical *** Salicylic acid:3-nitrobenzamide（SA-3NBZ）cocrystals with stoichiometric diversity at molar ratio of 1:1 and 2:2 were discovered using the combination of differential scanning calorimetry（DSC）and hot stage microscopy（HSM）.Single crystal X-ray diffraction analysis confirmed this ***

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