Electrons dual nature

ABSTRACT This article concerns various foundational aspects of the periodic system of the elements. These issues include the dual nature of the concept of an "element" to include element as a "basic substance" and as a "simple substance." We will discuss the question of whether there is an optimal form of the periodic table, including whether the left-step table fulfils this role. We will also discuss the derivation or explanation of the [n + , n] or Madelung rule for electron-shell filling and whether indeed it is important to attempt to derive this rule from first principles. In particular, we examine the views of two chemists, Henry Bent and Eugen Schwarz, who have independently addressed many of these issues. 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109 959-971, 2009... 

That light has a dual nature and behaves either like a wave or like a stream of particle-like photons is a fact we must accept, although it is nonintuitive. But remember, we have no direct experience of the behavior of very small particles such as electrons. Which model we use depends on the observations we are making. The wave model is appropriate when we are considering diffraction and interference experiments, but the particle (photon) model is essential when we are considering the interaction of light with individual atoms or molecules. 

Check out the video clip on the dual nature of electrons at www.brightredbooks.net... 

A class of partial differential equations first proposed by Erwin Schrodinger in 1926 to account for the so-called quantized wave behavior of molecules, atoms, nuclei, and electrons. Solutions to the Schrodinger equation are wave functions based on Louis de Broglie s proposal in 1924 that all matter has a dual nature, having properties of both particles and waves. These solutions are... 

Quantum mechanics, which replaced the old quantum theory, was not easy to interpret. It conceived of both light and particles as having a dual nature. They were sometimes observed to be waves and sometimes particles, depending on the type of experiment that one performed. For example, the electron seemed sometimes to be a particle and sometimes a packet of waves. Furthermore, quantum mechanics described the subatomic world in terms of probabilities. 

It does not provide much historical perspective on the development of quantum mechanics. Subjects such as the photoelectric effect, black-body radiation, the dual nature of electrons and photons, and the Davisson and Germer experiments are not even discussed. 

This dual nature of light appears puzzling to most students of this field, and cannot be resolved by any simple picture. From our point of view it is sufficient to consider that light is a stream of photons which travels in a straight line at constant velocity c (c = 3 X 108 ms-1). Each photon has an electric vector E and a magnetic vector H that allow interactions with electrons and nuclei through electric and magnetic forces. 

The experimental evidence discussed so far in this chapter leaves no possible doubt for the dual nature of electromagnetic radiation. It does not however make it easy to understand. How can something behave sometimes as waves, sometimes as particles This question will be raised again in connection with electrons and other microscopic particles in Chapter 2, and the difficulties discussed in more detail there (see Section 2.4). At this point, it is appropriate to discuss some ideas which, without giving a complete answer, go part of the way towards one. 

During this same period de Broglie s brother Maurice was studying experimental physics, and he was particularly interested in x rays. The brothers frequently discussed x rays, and their dual nature (both wavelike and particle-like behavior) suggested to Louis that this same particle-wave duality might also apply to particles such as electrons. 

The electron which responds to both quantum and classical potential fields exhibits this dual nature in its behaviour. Like a photon, an electron spreads over the entire region of space-time permitted by the boundary conditions, in this case stipulated by the classical potential. At the same time it also responds to the quantum field and reaches a steady, so-called stationary, state when the quantum and classical forces acting on the electron, are in balance. The best known example occurs in the hydrogen atom, which is traditionally described to be in the product state tpH = ipP ipe, hence with broken holistic symmetry. In many-electron atoms the atomic wave function is further fragmented into individual quantum states for pairs of electrons with paired spins. 

To understand the dual nature of light and the relationships among its energy, frequency, and wavelength 4.5 To write electronic configurations in a shorter notation, using the concepts of shells, subshells, and orbitals... 

Many organoantimony(III) halides are Lewis amphoteric. They have acidic sites on the Sb atoms and they are also basic through the lone pairs of electrons on the halogen atoms. A frequently encountered consequence of this dual nature is the formation of coordination polymers in the solid state. The resulting structures formed through self-assembly of molecules were considered in a book and in a review article. The Lewis acidity of organoantimony halides is also reflected in the tendency to form stable adducts with neutral donors or with halide anions. The 1 1 adduct (2) is formed by reaction of methylantimony dichloride with 2,2 -bipyridine. " ... 

Particles in motion, such as neutrons and electrons, may be used as an alternative to x-rays. They produce images of crystal structures in reciprocal space because of their dual nature as follows from quantum mechanics,... 

The effect of substituents in the benzene ring provides an interesting example of the dual nature of carbanion addition to carbonyl groups. When an electron-releasing group is conjugated with the aldehyde function, a resonance form such as (XIV) apparently lowers the usual positive charge on the carbonyl carbon atom to a point where the addition... 

Each electron seems to have a dual nature in which both and ... 

An understanding of the mechanisms of the reactions in electrodics is provided by physical electrochemistry through the analysis of the electronic and ionic phases. For the first phase, the electronic character of the metals is important and hence solid state physics comes into focus. The quantal characteristic of the metal conductor defines the surface structure properties that are dealt by quantum electrochemistry. The concept of quantum particles is one of the main considerations of this chapter. The properties of the dual nature of this corpuscular wave produce equivocal understanding even in electrocatalysis. When a beam of electrons passes through a solid, the effective mass is the real quantity to be considered in the calculations, since the interactions of the electron with a nucleus are shielded by strong electrostatic interactions. 

---