Question: What is the effect of a quantized electron bond on an atom?
About the article "Quantum", section "Abstract".

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An electron can be "bound" to the nucleus of an atom by the attractive Coulomb force.
A system of one or more electrons bound to a nucleus is called an atom.
If the number of electrons is different from the nucleus' electrical charge, such an atom is called an ion.
The wave-like behavior of a bound electron is described by a function called an atomic orbital.
Each orbital has its own set of quantum numbers such as energy, angular momentum and projection of angular momentum, and only a discrete set of these orbitals exist around the nucleus.
According to the Pauli exclusion principle each orbital can be occupied by up to two electrons, which must differ in their spin quantum number.
Electrons can transfer between different orbitals by the emission or absorption of photons with an energy that matches the difference in potential.
Other methods of orbital transfer include collisions with particles, such as electrons, and the Auger effect.
To escape the atom, the energy of the electron must be increased above its binding energy to the atom.
This occurs, for example, with the photoelectric effect, where an incident photon exceeding the atom's ionization energy is absorbed by the electron.
The orbital angular momentum of electrons is quantized.
Because the electron is charged, it produces an orbital magnetic moment that is proportional to the angular momentum.
The net magnetic moment of an atom is equal to the vector sum of orbital and spin magnetic moments of all electrons and the nucleus.
The magnetic moment of the nucleus is negligible compared with that of the electrons.
The magnetic moments of the electrons that occupy the same orbital (so called, paired electrons) cancel each other out.
The chemical bond between atoms occurs as a result of electromagnetic interactions, as described by the laws of quantum mechanics.
The strongest bonds are formed by the sharing or transfer of electrons between atoms, allowing the formation of molecules.
Within a molecule, electrons move under the influence of several nuclei, and occupy molecular orbitals; much as they can occupy atomic orbitals in isolated atoms.
A fundamental factor in these molecular structures is the existence of electron pairs.
These are electrons with opposed spins, allowing them to occupy the same molecular orbital without violating the Pauli exclusion principle (much like in atoms).
Different molecular orbitals have different spatial distribution of the electron density.
For instance, in bonded pairs (i.e.
in the pairs that actually bind atoms together) electrons can be found with the maximal probability in a relatively small volume between the nuclei.
On the contrary, in non-bonded pairs electrons are distributed in a large volume around nuclei. 
The Schrödinger equation predicts that if certain properties of a system are measured, the result may be "quantized", meaning that only specific discrete values can occur.
One example is "energy quantization": the energy of an electron in an atom is always one of the quantized energy levels, a fact discovered via atomic spectroscopy.
(Energy quantization is discussed below.)
Another example is quantization of angular momentum.
This was an "assumption" in the earlier Bohr model of the atom, but it is a "prediction" of the Schrödinger equation.
Another result of the Schrödinger equation is that not every measurement gives a quantized result in quantum mechanics.
For example, position, momentum, time, and (in some situations) energy can have any value across a continuous range. 
Characteristic X-rays are emitted when outer-shell electrons fill a vacancy in the inner shell of an atom, releasing X-rays in a pattern that is "characteristic" to each element.
Characteristic X-rays were discovered by Charles Glover Barkla in 1909, who later won the Nobel Prize in Physics for his discovery in 1917.
Characteristic X-rays are produced when an element is bombarded with high-energy electrons.
When a high-energy electron (the incident electron) strikes a bound electron (the target electron) in an atom, the target electron is ejected from the inner shell of the atom.
After the electron has been ejected, the atom is left with a vacant energy level, also known as a core hole.
Outer-shell electrons then fall into the inner shell, emitting quantized photons with an energy level equivalent to the energy difference between the higher and lower states.
Each element has a unique set of energy levels, and thus the transition from higher to lower energy levels produces X-rays with frequencies that are characteristic to each element.
When an electron falls from the L shell to the K shell, the X-ray emitted is called a K-alpha X-ray.
Similarly, when an electron falls from the M shell to the K shell, the X-ray emitted is called a K-beta X-ray.
Sometimes, however, instead of releasing the energy in the form of an X-ray, the energy can be transferred to another electron, which is then ejected from the atom.
This is known as the Auger effect, and the second ejected electron is known as an Auger electron. 
Atomic electron transition is a change of an electron from one quantum state to another within an atom or artificial atom.
It appears discontinuous as the electron "jumps" from one energy level to another in a few nanoseconds or less.
It is also known as atomic transition, quantum jump, or quantum leap.
Electron transitions cause the emission or absorption of electromagnetic radiation in the form of quantized units called photons.
Their statistics are Poissonian, and the damping of statistic values of time between jumps is exponential on average.
The damping time constant (which ranges from nanoseconds to a few seconds) relates to the natural, pressure, and field broadening of spectral lines.
The farther the electron jumps, the shorter the wavelength of the photon emitted, meaning they emit different colors based on how far they jump.
Although changes of quantum state occur on the submicroscopic level, in popular discourse, the term "quantum leap" refers to a large increase. 
In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction.
Behind this, one finds the fundamental notion that a physical property may be "quantized," referred to as "the hypothesis of quantization".
This means that the magnitude can take on only certain discrete values.
A photon is a single quantum of light, and is referred to as a "light quantum".
The energy of an electron bound to an atom is quantized, which results in the stability of atoms, and hence of matter in general.
As incorporated into the theory of quantum mechanics, this is regarded by physicists as part of the fundamental framework for understanding and describing nature at the smallest length-scales.