Molecular fragments or chemical bonds

The classical (modulus/probability) and nonclassical (phase/current) components of molecular states are reexamined and their information contributions are summarized. The state and information continuity relations are discussed and a nonclassical character of the resultant gradient information source is emphasized. The states of noninteracting and interacting subsystems in the model donor-acceptor reactive system are compared and configurations of the mutually-closed and -open equidensity orbitals are tackled. The density matrices for subsystems in reactive complexes are used to describe the entangled molecular fragments and electron communications in donor-acceptor systems which determine the entropic multiplicity and composition of chemical bonds between reactants.

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Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052869 ◽

1974 ◽

Vol 32 ◽

pp. 570-571

Author(s):

R. H. Duff

Keyword(s):

Species Identification ◽

Valence Electron ◽

Chemical Species ◽

X Rays ◽

Chemical Bonds ◽

Small Shift ◽

X Ray ◽

Electron Transitions ◽

Peak Energy ◽

Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

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Synthesis and polymerization ability investigation of new methacrylic monomers with azomethine molecular fragments

Polymer materials and technologies ◽

10.32864/polymmattech-2016-2-4-57-61 ◽

2016 ◽

Vol 2 (4) ◽

pp. 57-61 ◽

Cited By ~ 1

Author(s):

V.M Ovdenko ◽

A.Yu, Kolendo

Keyword(s):

Molecular Fragments ◽

Methacrylic Monomers

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Use of a Method of Small X-Ray Line Shifts to Investigate the Electronic Structure of Crystal Chemical Bonds

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0113.197406v.0360 ◽

1974 ◽

Vol 113 (6) ◽

pp. 360 ◽

Cited By ~ 1

Author(s):

O.M. Sumbaev ◽

E.V. Petrovich ◽

Yu.P. Smirnov ◽

I.M. Band ◽

Aleksandr I. Smirnov

Keyword(s):

Electronic Structure ◽

Crystal Chemical ◽

Chemical Bonds ◽

X Ray ◽

Small X

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Quasi-Barrierless Submolecular Motion in Mechanically Interlocked Carbon Nanotubes

10.26434/chemrxiv.12136248 ◽

2020 ◽

Author(s):

Julia Villalva ◽

Belén Nieto-Ortega ◽

Manuel Melle-Franco ◽

Emilio Pérez

Keyword(s):

Density Functional ◽

Close Contact ◽

Tight Binding ◽

Energetic Cost ◽

Molecular Fragments ◽

Activation Barriers ◽

Flat Surfaces ◽

Different Types ◽

Atomically Flat ◽

Derivatives Of

The motion of molecular fragments in close contact with atomically flat surfaces is still not fully understood. Does a more favourable interaction imply a larger barrier towards motion even if there are no obvious minima? Here, we use mechanically interlocked rotaxane-type derivatives of SWNTs (MINTs) featuring four different types of macrocycles with significantly different affinities for the SWNT thread as models to study this problem. Using molecular dynamics, we find that there is no direct correlation between the interaction energy of the macrocycle with the SWNT and its ability to move along or around it. Density functional tight-binding calculations reveal small (<2.5 Kcal·mol-1) activation barriers, the height of which correlates with the commensurability of the aromatic moieties in the macrocycle with the SWNT. Our results show that macrocycles in MINTs rotate and translate freely around and along SWNTs at room temperature, with an energetic cost lower than the rotation around the C−C bond in ethane.<br>

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