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Xenon atomic emission spectrum8/28/2023 ![]() The motion is so fast that it cannot be resolved by the eye, one sees a sequence of nodes and antinodes. The picture below shows how a string vibrates in the lowest three normal modes. The superposition of different normal modes is heard as superposition of ground- and overtones. These are called normal modes or eigenmodes. It is always possible to describe the motion of the string as a superposition of simple modes which have the peculiar property that all parts of the string move sinusoidally with the same frequency and phase. The exact way how a guitar's string vibrates depends on the spot where it has been plucked. Some simple examples will be used to demonstrate general properties of oscillating systems, standing waves in particular. For us it is important to realize that the electron forms some kind of standing wave. This is described in detail in all textbooks on quantum mechanics. Its possible wavefunctions can be obtained as solutions of the Schrödinger equation. Its nucleus carries one unit of positive elementary charge and thus binds only one electron to it. The hydrogen atom is the simplest of all atoms. Wavefunctions are used to calculate observable quantities in particular, the probability to find the (pointlike) particle in some volume is given by the squared value of the wavefunction integrated over the volume. Thus the electrons bound by electric force to an atomic nucleus (which contains almost all of the atom's mass) must be considered to be waves. The fact that these apparently contradictory attributes are compatible in matter waves and also in light (photons) is hard to understand, but all experimental data point out that this is the case. Waves always have some spatial extension, while one may imagine the elementary, indivisible particles as being “pointlike”. While we cannot dive into mathematical details here, the basic principles shall be sketched. Quantum theory is, so to say, the mathematical formulation of particle–wave duality. Only with quantum theory atomic structure can be understood. Nevertheless, to understand how the colours which surround us come about, one needs some basic knowledge on the smallest parts of matter. If the light of the sun is spread out into different colours by a simple glass prism, the narrow absorption lines cannot be seen. Neon, which gives red colour in a gas discharge, is a colourless gas. The aurora borealis (northern light) is very rare at our latitudes, and to appreciate the colours of cosmic objects, powerful telescopes are necessary. Neon signs (or other gas discharge tubes) as used for advertising, sodium or mercury vapour lamps show atomic emission the colours of fireworks are due to it. Light emitted or absorbed by single atoms contributes only very little to the colours of our surroundings. The same file with adapted formatting can be found here. (orig.Atomic spectra The html formatting and custom instructions have been disabled on this server. A list of wavelengths for observed laser transitions showing the present classifications and a discussion of the determination of the ionization potential of Xe II concludes the paper. The latter are compared to recent experimental measurements. We present an analysis of the 5s photoelectron satellite spectrum of Xe based on our calculated eigenvector compositions and calculations of transition probabilities for ground state transitions as well as lifetimes for the 6p levels. The former is the better coupling scheme for Xe II. The levels have been named in jK and for many levels also in LS coupling. A least-squares fit to the 5p 46p configuration is also reported. We have carried out least-squares fits to the even configurations and report the resulting parameter values and eigenvector compositions. Also a number of g-factors have been determined for the first time and we give in total 75 g-factors. We report 161 energy levels which have been identified on the basis of classifications of 950 lines. The latter has kindly placed the original wavelength list covering the wavelength range 10220-390 A at our disposal. This spectrum has been reanalyzed on the basis of the wavelength material published by Drs J. We present a revised analysis of the spectrum of singly ionized xenon, Xe II. ![]()
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