Short and long range contributions to the inductive effect in π electron systems

It is shown that the inductive effect of a substituent can have contributions of both exchange and Coulomb type, but that the exchange terms can be treated empirically as though they arise from a short-range field effect. Calculations of the exchange terms for the halogens and the methyl group are in accord with the empirical values of inductive parameters deduced from spectroscopy. Evidence is given that for a methyl group the inductive perturbation is almost entirely of short range type and is probably dominated by the exchange terms but for a chloro substituent both the short range exchange repulsion and the long range Coulomb attraction are important.

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Scattering and Its Applications to Various Atomic Processes: Elastic Scattering, Resonances, Photoabsorption, Rydberg States, and Opacity of the Atmosphere of the Sun and Stellar Objects

Atoms ◽

10.3390/atoms8040078 ◽

2020 ◽

Vol 8 (4) ◽

pp. 78

Author(s):

Anand K. Bhatia

Keyword(s):

Elastic Scattering ◽

Long Range ◽

Short Range ◽

Bound States ◽

Rydberg States ◽

Stellar Atmospheres ◽

Electron Systems ◽

Short Range Correlations ◽

Hybrid Theory ◽

Scattering Resonances

A scattering process can be a natural process or a process carried out in a laboratory. The scattering of particles from targets has resulted in important discoveries in physics. We discuss various scattering theories of electrons and positrons and their applications to elastic scattering, resonances, photoabsorption, excitation, and solar and stellar atmospheres. Among the most commonly employed approaches are the Kohn variational principle, close-coupling approximation, method of polarized orbitals, R-matrix formulation, and hybrid theory. In every formulation, an attempt is made to include exchange, long-range and short-range correlations, and to make the approach variationally correct. The present formulation, namely, hybrid theory, which is discussed in greater detail compared to other approximations, includes exchange, long-range correlations, and short-range correlations at the same time, and is variationally correct. It was applied to calculate the phase shifts for elastic scattering, the resonance parameters of two-electron systems, photoabsorption in two-electron systems, excitation of atomic hydrogen by an electron and positron impact, and to study the opacity of the Sun’s atmosphere. Calculations of polarizabilities, Rydberg states, and bound states of atoms are also discussed.

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Structural basis of long-range to short-range synaptic transition in NHEJ

Nature ◽

10.1038/s41586-021-03458-7 ◽

2021 ◽

Author(s):

Siyu Chen ◽

Linda Lee ◽

Tasmin Naila ◽

Susan Fishbain ◽

Annie Wang ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Basis

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Comparison of short-range order in irradiated dysprosium titanates

npj Materials Degradation ◽

10.1038/s41529-021-00165-6 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Roman Sherrod ◽

Eric C. O’Quinn ◽

Igor M. Gussev ◽

Cale Overstreet ◽

Joerg Neuefeind ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Model ◽

Ion Irradiation ◽

Function Analysis ◽

Ion Beam ◽

Structural Response ◽

Heavy Ion ◽

Range Order ◽

Radiation Resistant

AbstractThe structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior.

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SHORT-RANGE AND LONG-RANGE ORDER OF TITANIUM IN Ti1+xS2

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1977738 ◽

1977 ◽

Vol 38 (C7) ◽

pp. C7-202-C7-206 ◽

Cited By ~ 3

Author(s):

R. MORET ◽

M. HUBER ◽

R. COMÈS

Keyword(s):

Long Range ◽

Short Range ◽

Range Order ◽

Long Range Order

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Polarization Coulomb field scattering with the electron systems in AlGaN/GaN heterostructure field-effect transistors

AIP Advances ◽

10.1063/5.0012615 ◽

2020 ◽

Vol 10 (7) ◽

pp. 075212

Author(s):

Guangyuan Jiang ◽

Yuanjie Lv ◽

Zhaojun Lin ◽

Yongxiong Yang ◽

Yang Liu ◽

...

Keyword(s):

Field Effect ◽

Field Effect Transistors ◽

Coulomb Field ◽

Electron Systems ◽

Polarization Coulomb Field Scattering ◽

Heterostructure Field Effect Transistors ◽

Gan Heterostructure

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Short range smectic order driving long range nematic order: example of cuprates

Scientific Reports ◽

10.1038/srep19678 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

R. S. Markiewicz ◽

J. Lorenzana ◽

G. Seibold ◽

A. Bansil

Keyword(s):

Long Range ◽

Short Range ◽

Nematic Order

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Long-range ?-type hydrogen bond in dimers CH2?HF, CH2O?H2O, and CH2O?NH3

International Journal of Quantum Chemistry ◽

10.1002/qua.20481 ◽

2005 ◽

Vol 103 (2) ◽

pp. 157-166 ◽

Cited By ~ 1

Author(s):

Rui Yan Li ◽

Zhi Ru Li ◽

Di Wu ◽

Xi Yun Hao ◽

Ru Jiao Li ◽

...

Keyword(s):

Hydrogen Bond ◽

Long Range ◽

Range Type ◽

Type Hydrogen Bond

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ANDERSON LOCALIZATION FOR A MULTIDIMENSIONAL MODEL INCLUDING LONG RANGE POTENTIALS AND DISPLACEMENTS

Reviews in Mathematical Physics ◽

10.1142/s0129055x02001193 ◽

2002 ◽

Vol 14 (03) ◽

pp. 273-302 ◽

Cited By ~ 3

Author(s):

HERIBERT ZENK

Keyword(s):

Long Range ◽

Anderson Model ◽

Anderson Localization ◽

Short Range ◽

Energy Interval ◽

Multidimensional Model ◽

Short Summary

We give a short summary on how to combine and extend results of Combes and Hislop [2] (short range Anderson model with additional displacements), Kirsch, Stollmann and Stolz [13] and [14] (long range Anderson model without displacements) to get localization in an energy interval above the infimum of the almost sure spectrum for a continuous multidimensional Anderson model including long range potentials and displacements.

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