Advances in Physical Chemistry最新文献_第3页

Hydrogen Abstraction from Fluorinated Ethyl Methyl Ether Systems by OH Radicals OH自由基从氟化乙基甲基醚体系中提取氢

Advances in Physical Chemistry Pub Date : 2016-02-10 DOI: 10.1155/2016/3740278

Curtis White, Jaime M. Martell

引用次数: 3

A Group Theoretical and Quantum Chemical Study of Electronic Absorption and Fluorescence, Vibrational Spectra, and Conformations of Trimethine Cyanine Dye Molecules 三甲基菁染料分子的电子吸收、荧光、振动光谱和构象的群理论和量子化学研究

Advances in Physical Chemistry Pub Date : 2016-01-18 DOI: 10.1155/2016/6737494

V. V. Solomko, P. Kondratenko, Y. Lopatkin

{"title":"A Group Theoretical and Quantum Chemical Study of Electronic Absorption and Fluorescence, Vibrational Spectra, and Conformations of Trimethine Cyanine Dye Molecules","authors":"V. V. Solomko, P. Kondratenko, Y. Lopatkin","doi":"10.1155/2016/6737494","DOIUrl":"https://doi.org/10.1155/2016/6737494","url":null,"abstract":"The energetic structures and conformations of trimethine cyanine dye molecules were investigated. For research, group theoretical and quantum chemical calculation methods were used. The theoretical group analysis of electronic and vibrational structure of molecules was carried out. Also, the energetic structures and conformations of the molecule of this dye were studied. Research shows that the investigated molecule may reside in three different conformational states, one of which is highly symmetric (symmetry ) and the other two with low symmetry. The third conformer is characterized by lowering of binding energy of the electronic system by 0.23 eV, and the long-wavelength absorption band is shifted to lower energies. Also the group theoretical analysis of the trimethine cyanine molecule had allowed systematizing the vibrational and electronic quantum transitions and identifying the bands in the absorption spectra. It is shown that the excitation of the molecule in -state causes trans-cis-isomerization. The presence of the barrier of ~0.1 eV allows the fluorescence process to compete with isomerization process, but isomerization causes a decrease in the fluorescence quantum yield of the dye.","PeriodicalId":7371,"journal":{"name":"Advances in Physical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88367958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decay of Metastable State with Account of Agglomeration and Relaxation Processes 考虑团聚和弛豫过程的亚稳态衰减

Advances in Physical Chemistry Pub Date : 2016-01-05 DOI: 10.1155/2016/9468050

V. Kurasov

引用次数: 0

DFT Study of a Novel Organic Film: The Structural versus Magnetic Effects 一种新型有机薄膜的DFT研究:结构与磁效应

Advances in Physical Chemistry Pub Date : 2015-11-29 DOI: 10.1155/2015/597584

S. Simonetti, A. Juan, G. Brizuela, S. Ulacco

{"title":"DFT Study of a Novel Organic Film: The Structural versus Magnetic Effects","authors":"S. Simonetti, A. Juan, G. Brizuela, S. Ulacco","doi":"10.1155/2015/597584","DOIUrl":"https://doi.org/10.1155/2015/597584","url":null,"abstract":"Unsaturated fatty acids have great interest by their activities as industrial materials in novel applications. In the present work, the cis-3-hexenoic acid (HA) adsorbed on the Ni(111) surface was studied by first-principles calculations using the Vienna Ab Initio Simulation Package (VASP). The most stable location for HA is presented on top site of Ni(111), although the energies are very similar for all the adsorption sites. The surface-molecule interaction takes place between the carboxyl group of HA and surrounding Ni atoms. The adsorption is weak and consequently the metal-molecule length is enhanced. The carboxyl group is elongated and weakened after adsorption giving rise to a shift in stretching frequencies. There are notable changes on the magnetic moments values of Ni surface atoms neighboring to the molecule that mainly induced magnetic moments on O and H atoms. Noticeable charge transfer occurs in 3d 4s, p Ni orbitals and 2s C, 2s p O, 1s H orbitals of carboxyl group. The surface presents positive work function changes after adsorption as a consequence of an electron back-donation. During interaction, the significance of the magnetic effects over the structural effects is evidenced. This sets the stage for a future adsorption process improvement based on the modification of the surface magnetic properties.","PeriodicalId":7371,"journal":{"name":"Advances in Physical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73860357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Geometry, Energy, and Some Electronic Properties of Carbon Polyprismanes: Ab Initio and Tight-Binding Study 碳多棱镜的几何、能量和一些电子性质:从头算和紧密结合研究

Advances in Physical Chemistry Pub Date : 2015-10-26 DOI: 10.1155/2015/506894

K. Katin, S. A. Shostachenko, A. I. Avkhadieva, M. Maslov

引用次数: 20

DFT Study on the Oxidative Addition of 4-Substituted Iodobenzenes on Pd(0)-Phosphine Complexes Pd(0)-膦配合物上4-取代碘苯氧化加成的DFT研究

Advances in Physical Chemistry Pub Date : 2015-10-04 DOI: 10.1155/2015/985268

Tímea R. Kégl, L. Kollár, T. Kégl

引用次数: 7

Revisiting Oxidative Dehydrogenation of Ethane by W Doping into MoVMn Mixed Oxides at Low Temperature 低温掺杂钨锰混合氧化物乙烷氧化脱氢研究

Advances in Physical Chemistry Pub Date : 2015-01-27 DOI: 10.1155/2015/102583

Mohammed H. Al-Hazmi, T. Odedairo, Adel S. Al-Dossari, YongMan Choi

引用次数: 0

Preparation of Zirconium Oxide Powder Using Zirconium Carboxylate Precursors 用羧酸锆前驱体制备氧化锆粉体

Advances in Physical Chemistry Pub Date : 2014-12-31 DOI: 10.1155/2014/429751

Mohammed H. Al-Hazmi, YongMan Choi, A. Apblett

引用次数: 10

Adsorption of Polyanion onto Large Alpha Alumina Beads with Variably Charged Surface 具有可变电荷表面的大α -氧化铝珠对聚阴离子的吸附

Advances in Physical Chemistry Pub Date : 2014-12-15 DOI: 10.1155/2014/460942

T. Pham, Motoyoshi Kobayashi, Y. Adachi

{"title":"Adsorption of Polyanion onto Large Alpha Alumina Beads with Variably Charged Surface","authors":"T. Pham, Motoyoshi Kobayashi, Y. Adachi","doi":"10.1155/2014/460942","DOIUrl":"https://doi.org/10.1155/2014/460942","url":null,"abstract":"Adsorption of strong polyelectrolyte, poly(styrenesulfonate), PSS, of different molecular weights onto large α-Al2O3 beads was systematically investigated as functions of pH and NaCl concentrations. The ultraviolet (UV) absorption spectra of PSS at different pH and salt concentrations confirmed that the structure of PSS is independent of pH. With the change of molecular weight from 70 kg/mol (PSS 70) to 1000 kg/mol (PSS 1000), adsorption amount of PSS increases and proton coadsorption on the surface of α-Al2O3 decreases at given pH and salt concentration. It suggests that higher molecular weight of PSS was less flat conformation than lower one. The adsorption density of PSS 70 and PSS 1000 decreases with decreasing salt concentrations, indicating that both electrostatic and nonelectrostatic interactions are involved. Experimental results of both PSS 70 and PSS 1000 adsorption isotherms onto α-Al2O3 at different pH and salt concentrations can be represented well by two-step adsorption model. The effects of molecular weight and salt concentration are explained by structure of adsorbed PSS onto α-Al2O3. The influence of added SDS on the isotherms is evaluated from the sequential adsorption. The SDS uptake onto α-Al2O3 in the presence of hemimicelles can prevent the adsorption of PSS at low concentration so that adsorption of PSS reduces with preadsorbed SDS.","PeriodicalId":7371,"journal":{"name":"Advances in Physical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86598412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 33

Evaluation of Density Matrix and Helmholtz Free Energy for Harmonic Oscillator Asymmetric Potential via Feynmans Approach 用费曼方法求谐振子不对称势的密度矩阵和亥姆霍兹自由能

Advances in Physical Chemistry Pub Date : 2014-11-02 DOI: 10.1155/2014/912054

P. Moonsri, A. Hutem

引用次数: 2