Group electronegativities from the bond critical point model

1992 ◽  
Vol 114 (5) ◽  
pp. 1652-1655 ◽  
Author(s):  
Russell J. Boyd ◽  
Susan L. Boyd
Keyword(s):  
Critical Point ◽  
Bond Critical Point ◽  
Point Model

Electronegativity and Bader's bond critical point

1992 ◽  
Vol 13 (7) ◽  
pp. 912-918 ◽  
Author(s):  
Sanchita Hati ◽  
Dipankar Datta
Keyword(s):  
Critical Point ◽  
Bond Critical Point

Bond length and the electron density at the bond critical point: XX, ZZ, and CZ bonds (X = Li-F, Z = Na-Cl)

2007 ◽  
Vol 29 (3) ◽  
pp. 367-379 ◽  
Author(s):  
Norberto Castillo ◽  
Katherine N. Robertson ◽  
S. C. Choi ◽  
Russell J. Boyd ◽  
Osvald Knop
Keyword(s):  
Bond Length ◽  
Critical Point ◽  
Electron Density ◽  
Bond Critical Point

Estimating the energy of intramolecular hydrogen bonds from1H NMR and QTAIM calculations

2016 ◽  
Vol 14 (47) ◽  
pp. 11199-11211 ◽  
Author(s):  
Andrei V. Afonin ◽  
Alexander V. Vashchenko ◽  
Mark V. Sigalov
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Critical Point ◽  
Intramolecular Hydrogen Bond ◽  
Bond Energy ◽  
Bond Critical Point ◽  
Hydrogen Bond Energy ◽  
H Nmr ◽  
Nmr Data ◽  
Intramolecular Hydrogen

Novel equations have been derived for the assessment of the E intramolecular hydrogen bond energy based on the experimental1H NMR data and the calculated QTAIM topologicalVandρparameters of the hydrogen bond critical point.

Experimental observation of charge-shift bond in fluorite CaF2

2017 ◽  
Vol 73 (4) ◽  
pp. 643-653 ◽  
Author(s):  
Marcin Stachowicz ◽  
Maura Malinska ◽  
Jan Parafiniuk ◽  
Krzysztof Woźniak
Keyword(s):  
Quantum Theory ◽  
Density Distribution ◽  
Critical Point ◽  
Electron Density ◽  
Closed Shell ◽  
Atoms In Molecules ◽  
Bond Critical Point ◽  
Ionic Radii ◽  
Bond Path ◽  
Charge Shift

On the basis of a multipole refinement of single-crystal X-ray diffraction data collected using an Ag source at 90 K to a resolution of 1.63 Å−1, a quantitative experimental charge density distribution has been obtained for fluorite (CaF2). The atoms-in-molecules integrated experimental charges for Ca2+and F−ions are +1.40 e and −0.70 e, respectively. The derived electron-density distribution, maximum electron-density paths, interaction lines and bond critical points along Ca2+...F−and F−...F−contacts revealed the character of these interactions. The Ca2+...F−interaction is clearly a closed shell and ionic in character. However, the F−...F−interaction has properties associated with the recently recognized type of interaction referred to as `charge-shift' bonding. This conclusion is supported by the topology of the electron localization function and analysis of the quantum theory of atoms in molecules and crystals topological parameters. The Ca2+...F−bonded radii – measured as distances from the centre of the ion to the critical point – are 1.21 Å for the Ca2+cation and 1.15 Å for the F−anion. These values are in a good agreement with the corresponding Shannon ionic radii. The F−...F−bond path and bond critical point is also found in the CaF2crystal structure. According to the quantum theory of atoms in molecules and crystals, this interaction is attractive in character. This is additionally supported by the topology of non-covalent interactions based on the reduced density gradient.

A Model Dielectric Function for Graphene from the Infrared to the Ultraviolet

2013 ◽  
Vol 1505 ◽  
Author(s):  
A. Boosalis ◽  
R. Elmquist ◽  
M. Real ◽  
N. Nguyen ◽  
M. Schubert ◽  
...  
Keyword(s):  
Critical Point ◽  
Dielectric Function ◽  
Spectral Range ◽  
Pyrolytic Graphite ◽  
Low Energy ◽  
Point Model ◽  
Exciton Resonance ◽  
Resonance Energies ◽  
Ellipsometry Data ◽  
Spectroscopic Ellipsometry Data

ABSTRACTA modified critical point model dielectric function for graphene is derived here and used to analyze spectroscopic ellipsometry data obtained over a wide spectral range from 3 to 9 eV. Critical point and exciton resonance energies are extracted and discussed. Our findings indicate that epitaxial graphene on SiC to exhibits equivalent exciton behavior to that of suspended graphene. We further apply our model dielectric function to evaluate dielectric function data for highly oriented pyrolytic graphite reported in the literature. Excellent agreement is found between the critical point model developed here and the literature data even for the low energy spectral range up to 1 eV.

Relationship between scald (Rhynchosporium secalis) and losses in grain yield of barley in Western Australia

1985 ◽  
Vol 36 (5) ◽  
pp. 655 ◽  
Author(s):  
TN Khan ◽  
MF D'Antuono
Keyword(s):  
Grain Yield ◽  
Critical Point ◽  
Western Australia ◽  
Field Experiments ◽  
Yield Loss ◽  
Growth Stages ◽  
Point Model ◽  
Percentage Yield ◽  
The Mean ◽  
Ripe Stage

The three commonly used techniques, viz. critical point model, area under the curve and multiple linear regression, were applied to study the relationship between scald infection and grain yield in field experiments conducted during 1979-1983 in Western Australia. In the preliminary analysis leaf three from the top and the mean of the top three leaves were found to be best correlated with yield. The three models did not dilfer greatly, presumably owing to the high correlations between scald at the milky ripe stage and at the earlier growth stages. The critical point model was chosen because of its simplicity. Percentage yield loss in combined data from all experiments showed a significant correlation (P < 0.001) with scald at the milky ripe stage and defined percentage yield loss in cultivars Clipper and Stirling to be about one-third of the mean scald damage on leaves 1 (flag), 2 and 3 at g.s. 75. Due to the range of trials in this analysis, it was suggested that this relationship may be applied to estimate yield loss from survey data in other parts of southern Australia, where scald is endemic.

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