New Approaches for Measuring Electrostatic Potentials and Charge Density Distributions in Working Devices Using Off-Axis and In-Line Electron Holography

The essential properties of monolayer silicene greatly enriched by boron substitutions are thoroughly explored through first-principles calculations. Delicate analyses are conducted on the highly non-uniform Moire superlattices, atom-dominated band structures, charge density distributions and atom- and orbital-decomposed van Hove singularities. The hybridized 2 p z –3 p z and [2s, 2 p x , 2 p y ]–[3s, 3 p x , 3 p y ] bondings, with orthogonal relations, are obtained from the developed theoretical framework. The red-shifted Fermi level and the modified Dirac cones/ π bands/ σ bands are clearly identified under various concentrations and configurations of boron-guest atoms. Our results demonstrate that the charge transfer leads to the non-uniform chemical environment that creates diverse electronic properties.

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Charge density distributions and electron scattering form factors of 25Mg, 27Al and 29Si nuclei

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v14i30.220 ◽

2019 ◽

Vol 14 (30) ◽

pp. 129-135

Author(s):

Lubna Abduljabbar Mahmood

Keyword(s):

Charge Density ◽

Explicit Form ◽

Electron Scattering ◽

Ground State ◽

Density Operator ◽

Form Factors ◽

Body Density ◽

Density Distributions ◽

Tail Part

An effective two-body density operator for point nucleon systemfolded with the tenser force correlations( TC's), is produced and usedto derive an explicit form for ground state two-body charge densitydistributions (2BCDD's) applicable for 25Mg, 27Al and 29Si nuclei. It isfound that the inclusion of the two-body TC's has the feature ofincreasing the central part of the 2BCDD's significantly and reducingthe tail part of them slightly, i.e. it tends to increase the probability oftransferring the protons from the surface of the nucleus towards itscenteral region and consequently makes the nucleus to be more rigidthan the case when there is no TC's and also leads to decrease the1/ 2r 2 of the nucleus. It is also found that the effect of the TC's and theeffect of increasing the values of  on the 2BCDD's, elasticelectron scattering form factors and r2 1/ 2 are in the same directionfor all considered nuclei.

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Errors in electron density maps and the use of integrated densities in the study of charge density distributions

Acta Crystallographica Section B ◽

10.1107/s0567740868003420 ◽

1968 ◽

Vol 24 (7) ◽

pp. 925-929 ◽

Cited By ~ 17

Author(s):

P. Coppens ◽

W. C. Hamilton

Keyword(s):

Charge Density ◽

Electron Density ◽

Density Distributions ◽

Density Maps

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Charge density studies on methylene blue – a potential anti-Alzheimer agent

Zeitschrift für Naturforschung B ◽

10.1515/znb-2017-0165 ◽

2018 ◽

Vol 73 (2) ◽

pp. 99-108 ◽

Cited By ~ 3

Author(s):

Peter Luger ◽

Birger Dittrich ◽

Leonard Benecke ◽

Hannes Sterzel

Keyword(s):

Methylene Blue ◽

Charge Density ◽

Molecular Electrostatic Potential ◽

Positive Charge ◽

Atomic Charges ◽

Charge Densities ◽

Density Distributions ◽

Atomic Properties ◽

Counter Ions ◽

Medical Interest

AbstractMotivated by the medical interest in methylene blue as potential anti-Alzheimer agent, the charge densities of three salt structures containing the methylene blue cation with nitrate (as dihydrate), chloride (as pentahydrate) and thiocyanate counter-ions were generated by application of the invariom formalism and examined. The so-obtained charge density distributions were analyzed using the QTAIM formalism to yield bond topological and atomic properties. The atomic charges on the methylene blue cation indicate a delocalized charge distribution; only a small positive charge on the sulfur atom was found. Electrostatic potentials mapped onto iso-surfaces of electron density for the cations, and for the methylene blue cations with anions, were compared. The effect of hydrogen disorder on the molecular electrostatic potential was investigated for the thiocyanate structure.

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