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The Intramolecular Spin-Spin Interactions in Ruthenium Complexes of Pyrazole Derivatives

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光谱学与光谱分析 2016年第11期36卷 3737-3745页

作者： Peter A.Ajibade Department of Chemistry University of Fort Hare

The spin-spin coupling can provide useful information for analysing the structure of a system and the extent of non-covalent bonds *** this study,we present the isotropic NMR properties and spinspin coupling involving ruthenium-ligand(Ru-L)bonds and other spin-spin interactions obtained from dft *** proton shift which in close proximity with the Ru and Cl(or O)atoms are characterised with lower and higher chemical shift *** Ru-Cl bond has longer bond length than all other Ru-L bonds,yet its spin-spin coupling is higher than others because of a very high contribution of PSO which is far higher than the contribution from FC *** all other Ru-L bonds,FC is the most significant Ramsey terms that define their spin-spin *** the isotropic and anisotropic shielding of the Hz of the pyrazole is lower than Hc of the cymene and the spin-spin coupling 3J(Hz…Hz)of the pyrazole are less than half of the 3J(Hc…Hc)of the cymene unit in the *** is a little increase in both the 3J(Hc…Hc)and 3J(Hz…Hz)spin-spin coupling in the hydrolysed complexes compare to the non-hydrolysed *** isotropic and anisotropic shielding tensor of Ru atoms increases in magnitude as the complexes get hydrolysed that could be ascribed to a more deshielding chemical environments.

关键词： NMR dft method Spin-spin coupling Interatomic distance Shielding tensors

Quantum Chemistry Investigation into the Distribution Properties of 2-Formamido-phenylacrylates in n-Octanol/Water System

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Chinese Journal of Structural Chemistry 2006年第3期25卷 265-270页

作者：赵惠明张幸川余菁王遵尧 School of Biological and Chemical Engineering Jiaxing University

Molecular property parameters of 16 2-formamido-phenylacryiates were calculated with Hartree-Fock and dft methods at six different levels. Using the molecular property parameters and dissolvability as theoretical descriptors, two quantitative correlation equations that could be used to predict lgKow were developed based on experimental lgKow data of 11 2-formamido-phenylacrylates. A three-parameter correlation equation posing the ability of predicting -lgSw value was computed at B3LYP/6-311G＊＊ level. The -lgSw values of five compounds that we have pre-designed were anticipated with the above equation, upon which lgKow were further calculated. The relativity （r^2≥0.94, q^2〉0.91, SD≤0.083） and prediction ability of obtained correlation equations in this work are more advantageous than those based on solvatochromism parameters.

关键词： 2-formamido-phenylacrylates linear solvation energy theory Hartree-Fock dft method QSAR distribution properties

Quantitative Correlation of the Acute Toxicity of Phenylthio-carboxylates with Their Structural and Thermodynamic Parameters by dft Calculation

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Chinese Journal of Structural Chemistry 2005年第2期24卷 145-150页

作者：韩香云王遵尧杨春生 Department of Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu 224003China Department of Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu 224003ChinaCollege of EnvironmentNanjing UniversityNanjingJiangsu 210093China

Phenylthio-carboxylates were computed at the B3LYP/6-31G* level with dft method. Based on linear solvation energy theory, the structural parameters were firstly taken as theoretical descriptors, and the corresponding linear solvation energy relationship (LSER) equation (r = 0.8989) to the toxicity of photobacterium phosphoreum (–lgEC50) was thus obtained. Then the structural and thermodynamic parameters were taken as theoretical descriptors, and as a result the other corresponding correlation equation (r = 0.9274) relating to –lgEC50 was provided. The two equations achieved in this work by B3LYP/6-31G* are both more advantageous than that from AM1.

关键词： acute toxicity linear solvation energy theory dft method quantitative structure-activity relationships (QSAR) aquatic life

2D-QSAR Studies on Triazolone Compounds Containing Benzenesulfonic Amide

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Chinese Journal of Structural Chemistry 2007年第8期26卷 883-888页

作者： WEI Qing-Li GAO Jun SUN Dao-Xing ZHANG Shu-Sheng College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China

The geometry structures of 6 triazolone compounds containing benzenesulfonic amide were fully optimized with dft （Density Functional Theory） method at the B3LYP/6-31G level, and the structural and electronic parameters of the compounds were calculated. The hydrophobic and topological parameters of the title compounds were calculated by HyperChem software. The mono- and bi-parametric models between the parameters and biological activity of the compounds were analyzed by Multiple Linear Regression method based on Hansch-Fujita model. The results show that the activities of the title compounds were increased with higher hydrophobic property logP and molecular volume V, lower molecular energy ETOTAL and electronegative of benzene ring Qph.

关键词： benzenesulfonic amide triazolone compounds 2D-QSAR dft method

Theoretical Study on the Coupling Mode of BrO-H2O and HOBr-H2O Complexes

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Chinese Journal of Chemistry 2005年第5期23卷 483-490页

作者：孙巧李桢曾小庆葛茂发五殿勋 GraduateSchoolofChineseAcademyofSciences Beijing100039China StateKeyLaboratoryforStructuralChemistryofUnstableandStableSpecies InstituteofChemistryChineseAcademyofSciencesBeijing100080China

The structural properties of two BrO  H 2 O (1 and 2) and three HOBr  H 2 O complexes (3, 4 and 5) have been investigated using four methods at the 6‐311++G(d,p) basis set level. In the two BrO  H 2 O complexes, the complex 2 with 2 A′ state, in which the interaction exists between Br atom of BrO and O atom of water, has a binding energies of about 11.37–13.92 J/mol and it is global minimum. As to HOBr  H 2 O complexes, the binding energies of 3 and 4 are about 16.30–21.32 J/mol and the stability order of the three HOBr  H 2 O complexes is: complex 3≈︁complex 4>complex 5.

关键词： dft method hydrogen bond weak interaction BrO?H2O and HOBr?H2O complex

IR and Raman Vibrational Assignments for Metal-free Phthalocyanine from Density Functional B3LYP/6-31G(d) method

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Chinese Journal of Chemistry 2004年第4期22卷 325-332页

作者：张宪玺鲍猛潘娜张跃兴姜建壮 Department of Chemistry Shandong University

Vibrational (IR and Raman) spectra for the metal-free phthalocyanine (H2Pc) have been comparatively investi-gated through experimental and theoretical methods. The frequencies and intensities were calculated at density functional B3LYP level using the 6-31G(d) basis set. The calculated vibrational frequencies were scaled by the fac-tor 0.9613 and compared with the experimental result. In the IR spectrum, the characteristic IR band at 1008 cm-1 is interpreted as C—N (pyrrole) in-plane bending vibration, in contrast with the traditional assigned NH in-plane or out-of-plane bending vibration. The band at 874 cm-1 is attributed to the isoindole deformation and aza vibration. In the Raman spectrum, the bands at 540, 566, 1310, 1340, 1425, 1448 and 1618 cm-1 are also re-interpreted. As-signments of vibrational bands in the IR and Raman spectra are given based on density functional calculations for the first time. The present work provides valuable information to the traditional empirical assignment and will be helpful for further investigation of the vibration spectra of phthalocyanine analogues and their metal complexes.

关键词： phthalocyanine dft method IR spectra Raman spectra

Change in^(7)Be half-life in host media

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Chinese Physics C 2021年第6期45卷 138-140页

作者： Farshid Gholamian Mohammad Mehdi Firoozabadi Reza Sarhaddi Department of Physics Faculty of SciencesUniversity of BirjandBirjandIran

First-principle calculations within the density functional theory framework are used to study the probability of electron capture for the^(7)Be *** this purpose,electron density at the^(7)Be nucleus is computed in Al,Au,Pd,Pt,and Pb *** results show that the half-life of^(7)Be is changed by implanting^(7)Be in host *** affinity of the media and confinement effects are responsible for the change in the half-life of^(7)Be ***,electric potential at the^(7)Be nucleus is *** show that variations in electric potential are usually consistent with those in electron density at the^(7)Be nucleus.

关键词： decay rate change confinement effect electron affinity effect dft method

Effects of electric fields on^(7)Be half-life

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Chinese Physics C 2021年第7期45卷 214-218页

作者： Farshid Gholamian Mohammad Mehdi Firoozabadi Reza Sarhaddi Department of Physics Faculty of SciencesUniversity of BirjandBirjandIran

First-principle calculations based on the density functional theory(dft)method are adopted to investigate the influence of a strong electric field on the^(7)Be ***,electronic structures of Be and BeO are examined in the presence of a homogeneous electric *** electron density at the nucleus is estimated upon the geometry *** computations for the Be metal indicate a 0.02%increase in the decay rate of the^(7)Be nucleus,corresponding to a 0.02%decrease in the^(7)Be half-life,both at 5.14 V/A(0.1 a.u.).Furthermore,it is determined that the decay rate of^(7)Be is not considerably altered up to 3.6 V/Åin the BeO *** results show that the screening energy of the electron can be dependent on the applied electric field ***,we predict variations in the Coulomb potential at the^(7)Be nucleus due to electric field application.

关键词： decay rate change electric field dft method

2D-and 3D-QSBR Study on the Relationship between the Structure and Biodegradation Property of Sulfonylurea Herbicides

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Chinese Journal of Structural Chemistry 2012年第12期31卷 1693-1700页

作者：韩香云石佳奇郑清张玉国张磊 School of Environmental Science and Engineering Yancheng Institute of Technology

Using dft method, 10 sulfonylurea herbicides were computed at the B3LYP/6- 31G＊ level. Based on linear solvation energy theory, the corresponding linear solvation energy relationship （LSER） equation （R2 -- 0.759） to the half-life time （T1/2） of biodegradation was obtained with the structural and thermodynamic parameters as theoretical descriptors. Furthermore, CoMSIA method was also applied to establish 3D models which reveal the fields influencing these properties. The relationship between the properties and the structure was obtained. And the related coefficient of the model is 0.952. Results showed the electronic property is important to affect the biodegradation of these compounds by analysis of the 2D and 3D models.

关键词： sulfonylurea herbicide biodegradation dft method CoMSIA