electro-, electr-, electri-

1. An average region around the nucleus of an atom, in which the electrons are predicted to be at certain states of excitation.
2. The group or system of electrons revolving around the nucleus of an atom; a cloud-like group of electrons.
3. In a vacuum tube, the area between the electrodes that contains a great number of relatively stationary electrons.

1. In a phase diagram one of several homogeneous phases that has a specific crystal structure and a specific valence electron-to-atom ratio.
2. An alloy of two metals in which a progressive change in composition is accompanied by a progression of phases, differing in crystal structure.

1. A configuration that shows the way in which the electrons in an atom occupy, in order of increasing energy, the available orbitals and spin states.
2. The orbital arrangement of an atom's electrons.

Negatively charged electrons are attracted to a positively charged nucleus to form an atom or an ion.

3. The arrangement of electrons in an atom, molecule, or other physical structure; such as, a crystal.
4. The specific distribution of electrons in atomic orbitals of atoms or or ions.

1. An instrument that increases the power of a microwave tube by submitting its electron beam to changing periods of speeding up and slowing down.
2. A microwave amplifier tube where electron bunching is produced by an electron beam projected parallel to a magnetic field and is also influenced by a transverse electric field produced by a signal generator.

1. A procedure in which two circuits in an electron tube transfer energy generated by the electron stream passing between the electrodes of one of the circuits.
2. A method of coupling electrical energy from one circuit to another through the electron stream in a vacuum tube.
3. A process of coupling or linking two circuits inside an electron tube, used primarily with multigrid tubes.

The electron stream passing between electrodes in one circuit transfers energy to electrodes in the other circuit.

1. A source of multiple charged heavy ions which uses microwave power to increase electron energy to extremely high levels in two magnetic-mirror confinement chambers connected in a series.
2. An electrode supplying current of charged heavy ions that uses microwave power to heat electrons to energies of tens of kilovolts in two magnetic mirror confinement chambers in a series.

Ions formed in the first chamber drift into the second chamber, where they become charged.

1. A circularly polarized wave found in a plasma that runs parallel to the magnetic field produced by electric currents outside the plasma.
2. A wave in a plasma that moves parallel to the magnetic field produced by currents outside the plasma at frequencies less than that of the electron cyclotron resonance, and which is circularly polarized, rotating in the same sense as electrons in the plasma; responsible for whistlers.

A whistler is defined as an effect that occurs when a plasma disturbance, caused by a lightning discharge, travels out along lines of magnetic force of the earth's field and is reflected back to its origin from a magnetic point on the earth's surface.

1. The number of electrons per a unit volume or in a unit volume.
2. The quantum mechanical probability density for an electron.

1. An instrument whose operation involves the motion of electrical charge carriers in a gas, semiconductor, or vacuum.
2. A device or tool in which conduction is principally by electrons moving through a vacuum, gas, or semiconductor; such as, in a crystal diode, electron tube, transistor, or selenium rectifier.

The change in the directions and intensities of a group of waves of electrons when they pass through crystalline matter: Electron diffraction is useful in the study of the structures of materials.

Electron diffraction refers to the bending of electromagnetic waves as they pass around corners or through holes smaller than the wavelengths of the waves themselves.

The occurrence or the technique of producing electron diffractions through the incidence of electrons on matter.

The bending of an electron stream which occurs when the electron diffraction travels through a medium; such as, very thin metal foil.

1. A device which produces an electron-diffraction pattern by focusing an electron beam onto a crystal specimen, allowing the user to examine the crystal structure of the sample.
2. An instrument related to the electron microscope, in which a beam of electrons strikes the sample, showing crystal pattern and other physical attributes on the resulting diffraction pattern: An electron diffractograph is used for chemical analysis, atomic structure determination, etc.

1. An action that describes the electron density in phase space (a spectral representation of physical space).
2. A function that produces the number of electrons per unit volume of phase space.

1. An electron donor in an oxidation-reduction (redox) reaction or a molecule or compound that gives up electrons in an oxidation-reduction reaction in which electrons are removed from one molecule or atom and given to another molecule or atom.
2. A chemical element that donates electrons to another compound.

It is a reducing agent which, because of its donating electrons, is itself oxidized in the process.

The movement of electrons in a definite direction through a conductor, as opposed to the haphazard transfer of energy from one electron to another electron by collision.

1. The release of electrons from a specific material into the surrounding area or space.

It may be caused by an electric field, light, heat, or impact chemical disintegration.

2. A liberation of electrons from a substance into a vacuum.

Since all substances consist of atoms and since all atoms contain electrons, any substance may emit electrons; usually, however, the term refers to the emission of electrons from the surface of a solid.

3. The freeing of electrons into space from the surface of a body under the influence of heat, light, impact, chemical disintegration, or a potential difference.