scholarly journals QUANTUM CHEMISTRY CALCULATIONS ON THE LATTICE INSTABILITIES OF HEXAHALOMET- ALLATES

1995 ◽  
Vol 44 (11) ◽  
pp. 1798
Author(s):  
ZHANG JIA-MING ◽  
LU WEI ◽  
SHEN XUE-CHU
Keyword(s):  
Quantum Chemistry ◽  
Quantum Chemistry Calculations

Novel thermally activated delayed fluorescence materials by high-throughput virtual screening: going beyond donor–acceptor design

2021 ◽  
Vol 9 (9) ◽  
pp. 3324-3333 ◽  
Author(s):  
Ke Zhao ◽  
Ömer H. Omar ◽  
Tahereh Nematiaram ◽  
Daniele Padula ◽  
Alessandro Troisi
Keyword(s):  
Virtual Screening ◽  
Quantum Chemistry ◽  
High Throughput ◽  
Delayed Fluorescence ◽  
Thermally Activated Delayed Fluorescence ◽  
Thermally Activated ◽  
Quantum Chemistry Calculations ◽  
Donor Acceptor ◽  
Molecular Semiconductors ◽  
High Throughput Virtual Screening

125 potential TADF candidates are identified through quantum chemistry calculations of 700 molecules derived from a database of 40 000 molecular semiconductors. Most of them are new and some do not belong to the class of donor–acceptor molecules.

scholarly journals Adsorption and Desorption Mechanisms of Rare Earth Elements (REEs) by Layered Double Hydroxide (LDH) Modified with Chelating Agents

2019 ◽  
Vol 9 (22) ◽  
pp. 4805 ◽  
Author(s):  
Shuang Zhang ◽  
Naoki Kano ◽  
Kenji Mishima ◽  
Hirokazu Okawa
Keyword(s):  
Rare Earth ◽  
Quantum Chemistry ◽  
Rare Earth Elements ◽  
Adsorption Capacity ◽  
Density Functional ◽  
Stable State ◽  
Experimental Result ◽  
Adsorption And Desorption ◽  
Adsorption Affinity ◽  
Quantum Chemistry Calculations

In order to obtain the adsorption mechanism and adsorption structures of Rare Earth Elements (REEs) ions adsorbed onto layered double hydroxides (LDH), the adsorption performance of LDH and ethylenediaminetetraacetic acid (EDTA) intercalated LDH for REEs was investigated by batch experiments and regeneration studies. In addition to adsorption capacity, the partition coefficient (PC) was also evaluated to assess their true performance metrics. The adsorption capacity of LDH increases from 24.9 μg·g−1 to 145 μg·g−1 for Eu, and from 20.8 μg·g−1 to 124 μg·g−1 for La by intercalating EDTA in this work; and PC increases from 45.5 μg·g−1·uM−1 to 834 μg·g−1·uM−1 for Eu, and from 33.6 μg·g−1·μM−1 to 405 μg·g−1·μM−1 for La. Comparison of the data indicates that the adsorption affinity of EDTA-intercalated LDH is better than that of precursor LDH no matter whether the concept of adsorption capacity or that of the PC was used. The prepared adsorbent was characterized by XRD, SEM-EDS and FT-IR techniques. Moreover, quantum chemistry calculations were also performed using the GAUSSIAN09 program package. In this calculation, the molecular locally stable state structures were optimized by density functional theory (DFT). Both the quantum chemistry calculations and the experimental data showed that REEs ions adsorbed by EDTA-intercalated LDH are more stable than those adsorbed by precursor LDH. Furthermore, the calculation results of adsorption and desorption rates show that adsorption rates are larger for Eu(III) than for La(III), which agrees with the experimental result that Eu(III) has a higher adsorption ability under the same conditions. The LDHs synthesized in this work have a high affinity for removing REEs ions.

scholarly journals Quantum Chemistry Calculations on Binding Energies and Orbital Localization of Excitons in Organic Photovoltaic Semiconductors

2013 ◽  
Vol 25 (14) ◽  
pp. 8190-8194
Author(s):  
Hui Cao ◽  
Chaozhi Zhang ◽  
Tiancheng Feng ◽  
Jingjing Chen ◽  
Chenbo Fei ◽  
...  
Keyword(s):  
Quantum Chemistry ◽  
Binding Energies ◽  
Organic Photovoltaic ◽  
Quantum Chemistry Calculations

scholarly journals Unravelling the electronic structure and dynamics of an isolated molecular rotary motor in the gas-phase

2017 ◽  
Vol 8 (9) ◽  
pp. 6141-6148 ◽  
Author(s):  
Reece Beekmeyer ◽  
Michael A. Parkes ◽  
Luke Ridgwell ◽  
Jamie W. Riley ◽  
Jiawen Chen ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Quantum Chemistry ◽  
Gas Phase ◽  
Photoelectron Spectroscopy ◽  
Structure And Dynamics ◽  
Quantum Chemistry Calculations ◽  
Anion Photoelectron Spectroscopy ◽  
Rotary Motor

Anion photoelectron spectroscopy and quantum chemistry calculations are employed to probe the electronic structure and dynamics of a unidirectional molecular rotary motor anion in the gas-phase.

Quantum chemistry calculation of reaction pathways of carboxyl groups during coal self-heating

2017 ◽  
Vol 95 (8) ◽  
pp. 824-829 ◽  
Author(s):  
Xuyao Qi ◽  
Haibo Xue ◽  
Haihui Xin ◽  
Ziming Bai
Keyword(s):  
Quantum Chemistry ◽  
Oxidation Process ◽  
Hydrogen Abstraction ◽  
Thermal Parameters ◽  
Reaction Pathways ◽  
Carboxyl Groups ◽  
Heating Process ◽  
Hydrogen Atoms ◽  
Self Heating ◽  
Quantum Chemistry Calculations

During coal self-heating, reactions of carboxyl groups feature in the evolution of the spontaneous combustion of coal. However, their elementary reaction pathways during this process still have not been revealed. This paper selected the Ar–CH2–COOH as a typical carboxyl group containing structure for the analysis of the reaction pathways and enhancement effect on the coal self-heating process by quantum chemistry calculations. The results indicate that the hydrogen atoms in carboxyl groups are the active sites, which undergo the oxidation process and self-reaction process during coal self-heating. They both have two elementary reactions, namely (i) the hydrogen abstraction of –COOH by oxygen and the decarboxylation of the –COO· free radical and (ii) the hydrogen abstraction of –COOH and its pyrolysis. The total enthalpy change and activation energy of the oxidation process are 76.93 kJ/mol and 127.85 kJ/mol, respectively, which indicate that this process is endothermic and will occur at medium temperatures. For the hydrogen abstraction of –COOH by hydrocarbon free radicals, the thermal parameters are 53.53 kJ/mol and 56.13 kJ/mol, respectively, which has the same thermodynamic properties as the oxidation process. However, for the pyrolysis, the thermal parameters are –42.53 kJ/mol and 493.68 kJ/mol, respectively, and is thus exothermic and would not occur until the coal reaches high temperatures. They affect heat accumulation greatly, generate carbon dioxide, and provide new active centers for enhancing the coal self-heating process. The results would be helpful for further understanding of the coal self-heating mechanism.

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