What Are the Limits of Applicability for Graph Theoretic Descriptors in QSPR/QSAR? Modeling Dipole Moments of Aromatic Compounds with TOPS-MODE Descriptors

2002 ◽  
Vol 43 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Ernesto Estrada ◽  
Humberto González
Keyword(s):  
Aromatic Compounds ◽  
Dipole Moments ◽  
Qsar Modeling ◽  
Graph Theoretic

scholarly journals Combined Experimental and Theoretical Study on Photoionization Cross Sections of Benzonitrile and o/m/p-Cyanotoluene

2021 ◽  
Author(s):  
Jiabin Huang ◽  
Can Huang ◽  
Xiaoqing Wu ◽  
Qifeng Hou ◽  
Guangjun Tian ◽  
...  
Keyword(s):  
Cross Sections ◽  
Aromatic Compounds ◽  
Vacuum Ultraviolet ◽  
Theoretical Calculations ◽  
Dipole Moments ◽  
Decomposition Analysis ◽  
Interstellar Space ◽  
Hartree Fock ◽  
Photoionization Mass Spectrometry ◽  
Key Species

Toluene is one of the most abundant aromatic compounds in the atmosphere of Titan, and CN group has been regarded as an indicator for observing aromatic compounds in interstellar medium due to the large dipole moments resulted from the CN substituents. In the present work, the photoionization cross-sections (PICS) of benzonitrile and o/m/p-cyanotoluene, which are the products of CN + toluene were obtained at the photon energy ranging from ionization threshold to 14 eV combining experimental and theoretical methods. The synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) was employed, and theoretical calculations based on the frozen-core Hartree-Fock approximation and Franck-Condon simulations were carried out to cross-verify the measurements. In addition, the generalized charge decomposition analysis was used to investigate the characteristics of ionized molecular orbitals. Our results are valuable for quantifying these key species (especially by the SVUV-PIMS technique) and estimating related parameters such as dissociation rates in interstellar space.

scholarly journals The structure and reactivity of the halogenobenzens

1946 ◽  
Vol 185 (1000) ◽  
pp. 119-126
Keyword(s):  
Transition State ◽  
Charge Distribution ◽  
Aromatic Compounds ◽  
Inductive Effect ◽  
Dipole Moments ◽  
Aromatic Nucleus ◽  
Side Chain ◽  
Chain Reactions ◽  
State Resonance ◽  
Inductive Effects

The structure of the halogenobenzenes is described in terms of an inductive effect acting on the meta -positions and polarization between neighbouring atoms, in addition to the well-recognized mesomeric and inductive effects at the ortho - and para -positions. Data on the side-chain reactions of aromatic compounds are correlated with those on nitration (with recognition of the effect of transition-state resonance in the latter case) to provide estimates of the charge distribution in the aromatic nucleus. The dipole moments of the halogenobenzenes are calculated.

QSAR modeling of acute toxicity on mammals caused by aromatic compounds: the case study using oral LD50 for rats

2010 ◽  
Vol 12 (5) ◽  
pp. 1037 ◽  
Author(s):  
Bakhtiyor Rasulev ◽  
Hrvoje Kušić ◽  
Danuta Leszczynska ◽  
Jerzy Leszczynski ◽  
Natalija Koprivanac
Keyword(s):  
Acute Toxicity ◽  
Aromatic Compounds ◽  
Qsar Modeling

scholarly journals Combined Experimental and Theoretical Study on Photoionization Cross Sections of Benzonitrile and o/m/p-Cyanotoluene

2021 ◽  
Author(s):  
Jiabin Huang ◽  
Can Huang ◽  
Xiaoqing Wu ◽  
Qifeng Hou ◽  
Guangjun Tian ◽  
...  
Keyword(s):  
Cross Sections ◽  
Aromatic Compounds ◽  
Vacuum Ultraviolet ◽  
Theoretical Calculations ◽  
Dipole Moments ◽  
Decomposition Analysis ◽  
Interstellar Space ◽  
Hartree Fock ◽  
Photoionization Mass Spectrometry ◽  
Key Species

Toluene is one of the most abundant aromatic compounds in the atmosphere of Titan, and CN group has been regarded as an indicator for observing aromatic compounds in interstellar medium due to the large dipole moments resulted from the CN substituents. In the present work, the photoionization cross-sections (PICS) of benzonitrile and o/m/p-cyanotoluene, which are the products of CN + toluene were obtained at the photon energy ranging from ionization threshold to 14 eV combining experimental and theoretical methods. The synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) was employed, and theoretical calculations based on the frozen-core Hartree-Fock approximation and Franck-Condon simulations were carried out to cross-verify the measurements. In addition, the generalized charge decomposition analysis was used to investigate the characteristics of ionized molecular orbitals. Our results are valuable for quantifying these key species (especially by the SVUV-PIMS technique) and estimating related parameters such as dissociation rates in interstellar space.

Theoretical Study of Some Benzene Derivatives in Water

2008 ◽  
Vol 59 (9) ◽  
Author(s):  
Mihaela Dimitriu ◽  
Elena Filip ◽  
Ionel Humelnicu
Keyword(s):  
Aromatic Compounds ◽  
Theoretical Study ◽  
Dipole Moments ◽  
Point Of View ◽  
Electronic Transitions ◽  
Benzene Derivatives ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Influence Of Water ◽  
Total Energies

Using the HyperChem programme, the influence of water on the properties of some monosubstituted aromatic compounds was studied from the point of view of the intermolecular interactions. There have been estimated some physico-chemical parameters of the benzene, fluorobenzene, chlorobenzene, bromobenzene, iodobenzene, nitrobenzene, phenol and aniline when solved in water, surrounded by one or two solvation spheres. The boundary lengths, total energies, border levels energy, dipole moments, polarizabilities, wavelengths and the probabilities of the electronic transitions have been obtained.

scholarly journals An analysis of the dipole moments of some aromatic compounds

1934 ◽  
Vol 145 (854) ◽  
pp. 71-80 ◽  
Keyword(s):  
Dipole Moment ◽  
Aromatic Compounds ◽  
General Type ◽  
Dipole Moments ◽  
Aromatic Nucleus ◽  
Organic Substances ◽  
Benzene Derivatives ◽  
Electronic Theory ◽  
Disubstituted Benzene ◽  
Derivatives Of

The dipole moments of organic substances represent the resultants of a number of distinct moments within the molecule form which they must, as was pointed out by Sir J. J. Thomson, be obtainable by vector summation. This view was extended and further examined by Eucken and Meyer in 1929. It has been generally accepted and confirmed for a large variety of substances. The figures for para -disubstituted benzene derivatives of the type X. C 6 H 4 . Y are of particular importance for two reasons. First, it was anticipated by Ingold on the ground of the electronic theory of aromatic reactivity, that some deviation from the additive law might occur in this class of compound when Y was a group such as —NR 2 as a result of electronic displacements in the aromatic nucleus. When the necessary data became available by the measurements of Højendahl, a gross discrepancy of this kind appeared probable for p -nitraniline and p -nitroanisole, and this was specifically emphasized at that time. Secondly, a number of workers have recently made use of dipole moment data for aromatic ethers and sulphides of this same general type in order to compute the angle between the valencies of the characteristic atom (oxygen and sulphur) of the group Y.

Theoretical Investigation of the Second and Third Order Nonlinear Optical Properties of Some Fused Heterocyclic Aromatic Compounds

1999 ◽  
Vol 579 ◽  
Author(s):  
Mamoun M. Bader
Keyword(s):  
Optical Properties ◽  
Aromatic Compounds ◽  
Nonlinear Optical ◽  
Dipole Moments ◽  
Ring System ◽  
Basis Set ◽  
Third Order ◽  
First Order ◽  
Hartree Fock ◽  
Extended Basis

ABSTRACTWe report herein the results of coupled perturbed Hartree-Fock (CPHF) ab initio extended basis set calculations on the geometric structures, dipole moments, static first-order (α), second-order (β), and third-order polarizabilities (λ) of a series of fused heterocyclic aromatic compounds based on quinoline. The effects of the presence/absence of the heteroatom as well as the introduction of other substituents at various positions in the ring system on these molecular properties are described. The effect of the presence of N-oxide is also examined. Suggestions for the design of heterocyclic systems with enhanced polarizabilities are made.

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