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Electron energy loss spectroscopy (EELS) is a form of electron microscopy in which a material is exposed to a beam of electrons with a known, narrow range of kinetic energies. Some of the electrons will undergo inelastic scattering , which means that they lose energy and have their paths slightly and randomly deflected.
Electron excitation is the transfer of a bound electron to a more energetic, but still bound state. This can be done by photoexcitation (PE), where the electron absorbs a photon and gains all its energy [1] or by collisional excitation (CE), where the electron receives energy from a collision with another, energetic electron. [2]
An exciton is a bound state of an electron and an electron hole which are attracted to each other by the electrostatic Coulomb force resulting from their opposite charges. It is an electrically neutral quasiparticle regarded as an elementary excitation primarily in condensed matter, such insulators, semiconductors, some metals, and in some liquids.
Simple electron capture by itself results in a neutral atom, since the loss of the electron in the electron shell is balanced by a loss of positive nuclear charge. However, a positive atomic ion may result from further Auger electron emission. Electron capture is an example of weak interaction, one of the four fundamental forces.
For example, the antiparticle of the electron is the positron (also known as an antielectron). While the electron has a negative electric charge, the positron has a positive electric charge, and is produced naturally in certain types of radioactive decay. The opposite is also true: the antiparticle of the positron is the electron.
The positron or antielectron is the particle with an electric charge of +1e, a spin of 1/2 (the same as the electron), and the same mass as an electron.It is the antiparticle (antimatter counterpart) of the electron.
A diagram of a Rhodotron. The electron beam is in red. E is the electron gun, L is an electron lens, C is the radiofrequency cavity, and M is a bending magnet. A Rhodotron is an industrial electron accelerator first proposed in 1987 by J. Pottier of the French Atomic Energy Agency (CEA), [34] manufactured by Belgian company Ion Beam ...
Electron-withdrawing groups exert an "inductive" or "electron-pulling" effect on covalent bonds. The strength of the electron-withdrawing group is inversely proportional to the pKa of the carboxylic acid. [2] The inductive effect is cumulative: trichloroacetic acid is 1000x stronger than chloroacetic acid.