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Atomic physics (or atom physics) is the field of physics that studies atoms as isolated systems comprised of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and the processes by which these arrangements change. This clearly includes ions as well as neutral atoms and, unless otherwise stated, for the purposes of this discussion it should be assumed that the term atom includes ions. The first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density. ...
The Electron is a fundamental subatomic particle that carries an electric charge. ...
The nucleus (atomic nucleus) is the center of an atom. ...
The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...
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The term atomic physics is often associated with nuclear power and nuclear bombs, due to the synonymous use of atomic and nuclear in standard English. However, physicists distinguish between atomic physics - which deals with the atom as a system of electron(s) and a nucleus - and nuclear physics - which considers atomic nuclei alone. A nuclear power station. ...
The mushroom cloud of the atomic bombing of Nagasaki, Japan, in 1945 lifted nuclear fallout some 18 km (60,000 feet) above the epicenter. ...
Look up Synonym in Wiktionary, the free dictionary. ...
Standard English is a general term for a form of written and spoken English that is considered the model for educated people by native English speakers. ...
Nuclear physics is the branch of physics concerned with the nucleus of the atom. ...
A semi-accurate depiction of the helium atom. ...
As with many scientific fields, strict delineation can be highly contrived and atomic physics is often considered in the wider context of atomic, molecular, and optical physics. Physics research groups are usually so classified. Atomic, molecular, and optical physics is the study of matter-matter and light-matter interactions on the scale of single atoms or structures containing a few atoms. ...
Isolated atoms
Atomic physics always considers atoms in isolation - i.e. a model will consist of a single nucleus which may be surrounded by one or more bound electrons. It is not concerned with the formation of molecules (although much of the physics is identical) nor does it examine atoms in a solid state as condensed matter. It is concerned with processes such as ionization and excitation by photons or collisions with atomic particles. In chemistry, a molecule is an aggregate of two or more atoms in a definite arrangement held together by chemical bonds [1] [2] [3] [4] [5]. Chemical substances are not infinitely divisible into smaller fractions of the same substance: a molecule is generally considered the smallest particle of a pure...
It has been suggested that Solid state physics be merged into this article or section. ...
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Excitation is the amount of energy (energy in a general sense, not energy as defined in physics) that Curtis has. ...
While modelling atoms in isolation may not seem realistic, if one considers atoms in a gas or plasma then the time-scales for atom-atom interactions are huge in comparison to the atomic processes that we are concerned with. This means that the individual atoms can be treated as if each were in isolation because for the vast majority of the time they are. By this consideration atomic physics provides the underlying theory in plasma physics and atmospheric physics even though both deal with huge numbers of atoms. A gas is one of the four major phases of matter (after solid and liquid, and followed by plasma, that subsequently appear as a solid material is subjected to increasingly higher temperatures. ...
A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation A solar coronal mass ejection blasts plasma throughout the solar system. ...
A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation A solar coronal mass ejection blasts plasma throughout the solar system. ...
Atmospheric physics is the application of physics to the study of the atmosphere. ...
Electronic configuration Electrons form notional shells around the nucleus. These are naturally in a ground state but can be excited by the absorption of energy from light (photons), magnetic fields, or interaction with a colliding particle (typically other electrons). The excited electron may still be bound to the nucleus and should, after a certain period of time, decay back to the original ground state. The energy is released as a photon. There are strict selection rules as to the electronic configurations that can be reached by excitation by light - however there are no such rules for excitation by collision processes. Electron configuration is the arrangement of electrons in an atom, molecule or other body. ...
In physics, the ground state of a quantum mechanical system is its lowest-energy state. ...
The word light is defined here as electromagnetic radiation of any wavelength; thus, X-rays, gamma rays, ultraviolet light, microwaves, radio waves, and visible light are all forms of light. ...
In physics, especially in the context of quantum mechanics, a selection rule is a condition constraining the physical properties of the initial system and the final system that is necessary for a process to occur with a nonzero probability. ...
An electron may be sufficiently excited so that it breaks free of the nucleus and is no longer part of the atom. The remaining system is an ion and the atom is said to have been ionized having been left in a charged state. An ion is an atom or group of atoms that normally are electrically neutral and achieve their status as an ion by loss or addition of one or more electrons. ...
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History and developments The majority of fields in physics can be divided between theoretical work and experimental work and atomic physics is no exception. It is usually the case, but not always, that progress goes in alternate cycles from an experimental observation, through to a theoretical explanation followed by some predictions which may or may not be confirmed by experiment, and so on. Of course, the current state of technology at any given time can put limitations on what can be achieved experimentally and theoretically so it may take considerable time for theory to be refined. -
Clearly the earliest steps towards atomic physics was the recognition that matter was composed of atoms, in the modern sense of the basic unit of a chemical element. This theory was developed by the British chemist and physicist John Dalton in the 18th century. At this stage, it wasn't clear what atoms were although they could be described and classified by their properties (in bulk) in a periodic table. Various atoms and molecules as depicted in John Daltons A New System of Chemical Philosophy (1808). ...
The periodic table of the chemical elements A chemical element, often called simply an element, is a substance that cannot be decomposed or transformed into other chemical substances by ordinary chemical processes. ...
John Dalton John Dalton (September 6, 1766 – July 27, 1844) was an English chemist and physicist, born at Eaglesfield, near Cockermouth in Cumberland. ...
The periodic table of the chemical elements is a tabular method of displaying the chemical elements, first devised in 1869 by the Russian chemist Dmitri Mendeleev. ...
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The true beginning of atomic physics is marked by the discovery of spectral lines and attempts to describe the phenomenon, most notably by Joseph von Fraunhofer. The study of these lines led to the Bohr atom model and to the birth of quantum mechanics itself. In seeking to explain atomic spectra an entirely new mathematical model of matter was revealed. As far as atoms and their electron shells were concerned, not only did this yield a better overall description, i.e. the atomic orbital model, but it also provided a new theoretical basis for chemistry (quantum chemistry) and spectroscopy. Quantum mechanics is a physical science dealing with the behaviour of matter and waves on the scale of atoms and subatomic particles. ...
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. ...
Joseph von Fraunhofer Joseph von Fraunhofer (March 6, 1787 – June 7, 1826) was a German physicist. ...
The Bohr model of the atom The Bohr Model is a physical model that depicts the atom as a small positively charged nucleus with electrons in orbit at different levels, similar in structure to the solar system. ...
Fig. ...
The Atomic Orbital Model is the currently accepted model of the electrons in an atom. ...
Chemistry (from Greek χημεία khemeia[1] meaning alchemy) is the science of matter at the atomic to molecular scale, dealing primarily with collections of atoms, such as molecules, crystals, and metals. ...
Linus Pauling, as a pioneer of the valence bond theory, is one of the first quantum chemists. ...
Extremely high resolution spectrum of the Sun showing thousands of elemental absorption lines (fraunhofer lines) Spectroscopy is the study of matter and its properties by investigating light, sound, or particles that are emitted, absorbed or scattered by the matter under investigation. ...
Since the Second World War, both theoretical and experimental fields have advanced at a great pace. This can be attributed to progress in computing technology which has allowed bigger and more sophisticated models of atomic structure and associated collision processes. Similar technological advances in accelerators, detectors, magnetic field generation and lasers have greatly assisted experimental work. Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ...
A LASER (from the acronym of Light Amplification by Stimulated Emission of Radiation) is an optical source that emits photons in a coherent beam. ...
Significant atomic physicists - Pre quantum mechanics
- Post quantum mechanics
John Dalton John Dalton (September 6, 1766 – July 27, 1844) was an English chemist and physicist, born at Eaglesfield, near Cockermouth in Cumberland. ...
Joseph von Fraunhofer Joseph von Fraunhofer (March 6, 1787 – June 7, 1826) was a German physicist. ...
Janne Rydberg Johannes Robert Rydberg, commonly known as Janne Rydberg, (November 8, 1854 - December 28, 1919), was a Swedish physicist mainly known for devising the Rydberg formula, in 1888, which is used to predict the wavelengths of photons (of light and other electromagnetic radiation) emitted by changes in the energy...
Sir Joseph John Thomson, OM , FRS (December 18, 1756 – August 30, 1940) often known as J. J. Thomson, was an English physicist, the discoverer of the electron. ...
Sir David Bates, FRS (born 18 November 1916) was an Irish mathematician and physicist. ...
Niels (Henrik David) Bohr (October 7, 1885 – November 18, 1962) was a Danish physicist who made fundamental contributions to understanding atomic structure and quantum mechanics. ...
Max Born (December 11, 1882 in Breslau – January 5, 1970 in Göttingen) was a mathematician and physicist. ...
Clinton Joseph Davisson (22 October 1881–1 February 1958), was an American physicist. ...
Charlotte Froese Fischer (b. ...
Vladimir Aleksandrovich Fock (or Fok, Владимир Александрович Фок) (22 December 1898 - December 27, 1974) was a Soviet physicist, who did foundational work on quantum mechanics. ...
Douglas Rayner Hartree (March 27, 1897 - February 12, 1958) was an English mathematician and physicist most famous for the development of numerical analysis and its application to atomic physics. ...
Sir Harrie Stewart Wilson Massey (16 May 1908 - 27 November 1983) was a highly accomplished and influential mathematical physicist who worked primarily in the fields of atomic and atmospheric physics. ...
Sir Nevill Francis Mott (September 30, 1905 – August 8, 1996) was a British physicist. ...
Michael J. Seaton FRS Mike (born 16 January 1923) is a highly influential mathematician, atomic physicist and astronomer. ...
John Clark Slater (1900-1976) was a major physicist and theoretical chemist. ...
Joe has no friends what-so-ever Sir George Paget Thomson FRS (May 3, 1892 – September 10, 1975) was a Nobel-Prize-winning, English physicist who discovered the wave properties of the electron by electron diffraction. ...
See also Image File history File links Portal. ...
Fundamental atomic physics A quantum mechanical system can only be in certain states, so that only certain energy levels are possible. ...
This article discusses the concept of a wavefunction as it relates to quantum mechanics. ...
In chemistry, an atomic orbital is the region in which an electron may be found around a single atom. ...
The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...
Common units The International System of Units (symbol: SI) (for the French phrase Système International dUnités) is the most widely used system of units. ...
An electronvolt (symbol: eV) is the amount of energy gained by a single unbound electron when it falls through an electrostatic potential difference of one volt. ...
The Hartree energy (symbol Eh) is a physical constant used as atomic unit of energy, named after physicist Douglas Hartree. ...
Johannes Rydberg, commonly known as Janne Rydberg, (November 8, 1854 - December 28, 1919), was a Swedish physicist mainly known for devising the Rydberg formula, which is used to predict the wavelengths of photons (of light and other electromagnetic radiation) emitted by changes in the energy level of an electron in...
Wavenumber in most physical sciences is a wave property inversely related to wavelength, having units of inverse length. ...
Applications A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation A solar coronal mass ejection blasts plasma throughout the solar system. ...
Different stars have different atmospheres. ...
Atmospheric physics is the application of physics to the study of the atmosphere. ...
Atomic clock Chip-Scale Atomic Clock Unveiled by NIST An atomic clock is a type of clock that uses an atomic resonance frequency standard as its counter. ...
Related fields Quantum optics is a field of research in physics, dealing with the application of quantum mechanics to phenomena involving light and its interactions with matter. ...
Molecular physics is the study of the physical properties of molecules and of the chemical bonds between atoms that bind them into molecules. ...
References - Bransden, BH, Joachain, CJ (2002). Physics of Atoms and Molecules, 2nd Edition, Prentice Hall. ISBN 0-582-35692-X.
- Foot, CJ (2004). Atomic Physics. Oxford University Press. ISBN 0-19-850696-1.
External links - Atomic Physics on the Internet
- Atomic Physics Links
- JILA (Atomic Physics)
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