Local Temperature as a Chemical Reactivity Descriptor

Author(s):  
Chunna Guo ◽  
Xin He ◽  
Chunying Rong ◽  
Tian Lu ◽  
Shubin Liu ◽  
...  
2019 ◽  
Vol 32 (2) ◽  
pp. 401-407
Author(s):  
M. Dinesh Kumar ◽  
P. Rajesh ◽  
R. Priya Dharsini ◽  
M. Ezhil Inban

The quantum chemical calculations of organic compounds viz. (E)-1-(2,6-bis(4-chlorophenyl)-3-ethylpiperidine-4-ylidene)-2-phenyl-hydrazine (3ECl), (E)-1-(2,6-bis(4-chlorophenyl)-3-methylpiperidine-4-ylidene)-2-phenylhydrazine (3MCl) and (E)-1-(2,6-bis(4-chloro-phenyl)-3,5-dimethylpiperidine-4-ylidene)-2-phenylhydrazine (3,5-DMCl) have been performed by density functional theory (DFT) using B3LYP method with 6-311G (d,p) basis set. The electronic properties such as Frontier orbital and band gap energies have been calculated using DFT. Global reactivity descriptor has been computed to predict chemical stability and reactivity of the molecule. The chemical reactivity sites of compounds were predicted by mapping molecular electrostatic potential (MEP) surface over optimized geometries and comparing these with MEP map generated over crystal structures. The charge distribution of molecules predict by using Mulliken atomic charges. The non-linear optical property was predicted and interpreted the dipole moment (μ), polarizability (α) and hyperpolarizability (β) by using density functional theory.


2017 ◽  
Vol 8 (16) ◽  
pp. 3881-3887 ◽  
Author(s):  
Livia Giordano ◽  
Pinar Karayaylali ◽  
Yang Yu ◽  
Yu Katayama ◽  
Filippo Maglia ◽  
...  

Science ◽  
2021 ◽  
Vol 373 (6555) ◽  
pp. 638.5-639
Author(s):  
Yury Suleymanov

2017 ◽  
Vol 13 (1) ◽  
pp. 5937-5947
Author(s):  
Bendjeddou Amel ◽  
Tahar Abbaz ◽  
Abdelkrim Gouasmia ◽  
Didier Villemin

The chemical reactivity of four bis (trimethyltetrathiafulvalenyl) thiophene is determined by its potential (electronic) energy (hyper) surface. All the quantum chemical calculations have been carried out using DFT level of theory, B3LYP functional and 6-31G(d,p) as basis set. Molecular electrostatic potential (MEP) and HOMO-LUMO energy levels have been performed. The local reactivity descriptor such as Fukui function is also performed to determine the reactive sites within the title molecules. The chemometric methods PCA and HCA were employed to find the subset of variables that could correctly classify the compounds according to their reactivity.


2006 ◽  
Vol 759 (1-3) ◽  
pp. 109-110 ◽  
Author(s):  
P.K. Chattaraj ◽  
D.R. Roy ◽  
M. Elango ◽  
V. Subramanian

Author(s):  
A. M. Bradshaw

X-ray photoelectron spectroscopy (XPS or ESCA) was not developed by Siegbahn and co-workers as a surface analytical technique, but rather as a general probe of electronic structure and chemical reactivity. The method is based on the phenomenon of photoionisation: The absorption of monochromatic radiation in the target material (free atoms, molecules, solids or liquids) causes electrons to be injected into the vacuum continuum. Pseudo-monochromatic laboratory light sources (e.g. AlKα) have mostly been used hitherto for this excitation; in recent years synchrotron radiation has become increasingly important. A kinetic energy analysis of the so-called photoelectrons gives rise to a spectrum which consists of a series of lines corresponding to each discrete core and valence level of the system. The measured binding energy, EB, given by EB = hv−EK, where EK is the kineticenergy relative to the vacuum level, may be equated with the orbital energy derived from a Hartree-Fock SCF calculation of the system under consideration (Koopmans theorem).


Author(s):  
Thomas W. Shattuck ◽  
James R. Anderson ◽  
Neil W. Tindale ◽  
Peter R. Buseck

Individual particle analysis involves the study of tens of thousands of particles using automated scanning electron microscopy and elemental analysis by energy-dispersive, x-ray emission spectroscopy (EDS). EDS produces large data sets that must be analyzed using multi-variate statistical techniques. A complete study uses cluster analysis, discriminant analysis, and factor or principal components analysis (PCA). The three techniques are used in the study of particles sampled during the FeLine cruise to the mid-Pacific ocean in the summer of 1990. The mid-Pacific aerosol provides information on long range particle transport, iron deposition, sea salt ageing, and halogen chemistry.Aerosol particle data sets suffer from a number of difficulties for pattern recognition using cluster analysis. There is a great disparity in the number of observations per cluster and the range of the variables in each cluster. The variables are not normally distributed, they are subject to considerable experimental error, and many values are zero, because of finite detection limits. Many of the clusters show considerable overlap, because of natural variability, agglomeration, and chemical reactivity.


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