Quasimolecular defects as a unified microscopic basis of the glassy state

Dembovsky, S.A.

doi:10.1016/s0022-3093(87)80444-1

Cited by 8 publications

(6 citation statements)

References 10 publications

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“…(9) to (11), Figs. 2 to 4), the glass transition temperature T g with an increase in the cooling velocity shifts to a region of lower temperatures that correlates with the Ritland-Bartenev ratio [25,27]:…”

Section: Calculation Results and Empirical Relations For The Non-crysmentioning

confidence: 95%

Nanosized levels of the self-organized structures in the non-crystalline semiconductors As–S(Se) system

Mar'yan¹

2019

Semicond. phys., quantum electron. optoelectron.

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A synergetic model of the transition to a non-crystalline state is proposed, which enables us to investigate the temperature dependence of the microscopic parameters (meansquare displacements, the proportion of atoms in soft atomic configurations, power constants) under the influence of the external control parameter -the cooling velocity. Their analysis has been performed on the basis of experimental researches for noncrystalline semiconductors of the system As-S(Se). It has been shown that formation of self-organized structures in the non-crystalline solids is carried out in accordance with the technological conditions of obtaining as a method of the system self-organization. The dependence of the period and lifetime of self-organized structures on the cooling velocity has been studied. The established value of the period of spatial inhomogeneity L c ≈ 10…10 2 Å correlates with the nanosized midlle order in non-crystalline materials of the system As-S(Se) and decreases with increasing the cooling velocity.

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Section: Calculation Results and Empirical Relations For The Non-crysmentioning

confidence: 95%

Nanosized levels of the self-organized structures in the non-crystalline semiconductors As–S(Se) system

Mar'yan¹

2019

Semicond. phys., quantum electron. optoelectron.

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“…Table 2 presents the main parameters characterizing the surface of the films. The height of the surface roughness of the gradient structure with the bismuth is within the range of 0.4…2.5 nm [8,23,24]. Fig.…”

Section: Research Of Film Surface Morphologymentioning

confidence: 83%

Synergetics of the instability and randomness in formation of gradient modified semiconductor structures

Yurkovych¹

2018

Semicond. Phys. Quantum Electron. Optoelectron

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The criteria for formation of an inhomogeneous structure based on vitreous Ge 2 S 3 with modifiers Al, Bi, Pb, Te that are identified due to changes in the condensed medium (evaporation temperature, condensation velocity, increasing or decreasing the intensity of the fluctuations of the active field) have been determined. The article analyzes the obtained equations describing formation of inhomogeneous amorphous structures and taking into account the dynamics of the concentration of modifier owing to the source of the atomic flow of a chemical element, structural heterogeneity (availability of vacancies, micropores) and particle diffusion. Computer simulation of the source of the atomic flow of the modifier has been carried out, which makes it possible to form gradient structures with the predicted distribution of the chemical element according to the film thickness. Morphology of gradient structure surfaces and the mechanism of condensation of modifiers Al, Bi, Pb, Te with the amorphous matrix of Ge 2 S 3 have been ascertained.

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“… The latest version of Ψ‐scale after 6. The region for glass‐forming substances Ψ = 0.50–0.67 is shaded.…”

Section: Hypervalent Bonding In Glassmentioning

confidence: 99%

“…In the 1980s HVBs in the initial form of TCB was successively applied for interpretation of glass features 6, 11, 19–21. In parallel, original experiments on treatment of glass in a magnetic field were undertaken; they concerned viscous flow 22, 23, crystallization 24, and electrical switching 25.…”

Section: Bond Waves and Long‐range Order In Glassmentioning

confidence: 99%

Diastereoselective Formation of Host-Guest Complexes between a Series of Phosphate-Bridged Cavitands and Alkyl- and Arylammonium Ions Studied by Liquid Secondary-Ion Mass Spectrometry

2001

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The reactions occurring between a new class of cavitands that carry up to four dioxaphosphocin binding units and alkyl- and arylammonium ions was investigated by liquid secondary-ion mass spectrometry (LSIMS). As the cavitands existed as distinct diastereomers with different spatial orientation of their binding groups, these geometrical differences proved to have a dramatic influence on their chemical properties, including their ability to form host-guest complexes. In practice, only the cavitands that carry at least three P=O groups oriented toward the inside of the cavity were demonstrated to be strong ligands toward organic ammonium ions, whereas those with only two converging binding groups (either adjacent or opposite in the cavitand structure) still formed host-guest complexes, but they were much weaker. Adjacent binding sites proved to be more effective in interacting with organic ammonium ions than those lying in opposite positions. The isomers with no converging P=O groups did not act as molecular receptors. Even the isomer with one group oriented toward the inside of the cavity did not form host-guest complexes, as the absence of synergistic hydrogen bonding made the interaction from inside the cavity energetically equivalent (or even less favorable) to the outside binding. The presence in the cavitand structure of substituents with an electron-donating character proved to increase the proton affinity of the P=O binding groups and, consequently, their binding energy. The strong proton affinity of the cavitands led to the formation of stable host-guest complexes, as confirmed by the collisionally activated dissociation experiments. Effects of steric hindrance were weak, at least for the cavitands with three converging P=O groups. This confirmed that the cavity has a wide and readily accessible opening. The relative complexation constants were measured for the various guests, yielding scales of relative affinity toward each cavitand. These relative constants may represent thermodynamic values referred to the matrix used in LSIMS experiments, namely 3-nitrobenzyl alcohol (NBA), provided that kinetically controlled selvedge processes are negligible. Absolute complexation constants could not be obtained on account of the unknown pH and the protonation constant in the NBA matrix.

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Quasimolecular defects as a unified microscopic basis of the glassy state

Cited by 8 publications

References 10 publications

Nanosized levels of the self-organized structures in the non-crystalline semiconductors As–S(Se) system

Nanosized levels of the self-organized structures in the non-crystalline semiconductors As–S(Se) system

Synergetics of the instability and randomness in formation of gradient modified semiconductor structures

Diastereoselective Formation of Host-Guest Complexes between a Series of Phosphate-Bridged Cavitands and Alkyl- and Arylammonium Ions Studied by Liquid Secondary-Ion Mass Spectrometry

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