Atom
An atom is the smallest unit of matter that defines the chemical elements. Every solid, liquid, gas, and plasma is made up of neutral or ionized atoms. Atoms are very small: the size of atoms is measu...
Atom - Wikipedia
Iodine Molecular Movie
This movie, derived from LCLS data, shows an iodine molecule moving in the first 2 trillionths of a second after being excited by a laser pulse. The clouds o...
Scientists To Inject Fuel In Experimental Fusion Device
GREIFSWALD, Germany (AP) — Scientists in northeast Germany were poised to flip the switch Wednesday on an experiment they hope will advance the quest for nuclear fusion, considered a clean and safe fo...
BBC Earth - How many more chemical elements are there for us to find?
Since the 1930s, physicists have made dozens of new chemical elements. Could these discoveries continue forever?
CERN Collides Heavy Nuclei At New Record High Energy
One of the very first collisions recorded between two lead ions at the LHC's top energy. The energy in the center-of-mass system is approximately 1000 TeV. Todays events bring collisions physics into ...
Risky Fusion Power Study Pays Off By Bringing Plasma Close To Reactor Walls
The first major fusion collaboration between Chinese and US research teams has released a surprising finding on the future of magnetic confinement fusion: by lowering the distance between the plasma a...
Scientists Predict Cool New Phase Of Superionic Ice
Scientists have predicted a new phase of superionic ice, a special form of ice that could exist on Uranus and Neptune, in a theoretical study performed by a team of researchers at Princeton University...
UCLA Physicists Determine The Three-Dimensional Positions Of Individual Atoms For The First Time
Atoms are the building blocks of all matter on Earth, and the patterns in which they are arranged dictate how strong, conductive or flexible a material will be. Now, scientists at UCLA have used a pow...
Tiny Drops Of Early Universe 'Perfect' Fluid
First results from collisions of three-particle ions with gold nuclei reveal clear-cut evidence of primordial soup's signature particle flow. The Relativistic Heavy Ion Collider (RHIC), a particle col...
First Global Antineutrino Emission Map Highlights Earth's Energy Budget
The neutrino and its antimatter cousin, the antineutrino, are the tiniest subatomic particles known to science. These particles are byproducts of nuclear reactions within stars (including our sun), su...
Record-high Pressure Reveals Secrets Of Matter
At extremely high pressure even the innermost electrons in the atomic nuclei of the metal osmium begin to interact with each other, a phenomenon never witnessed before. The findings have been publishe...
Large Hadron Collider Discovers New Pentaquark Particle
Scientists at the Large Hadron Collider have announced the discovery of a new particle called the pentaquark. It was first predicted to exist in the 1960s but, much like the Higgs boson particle befor...
Time travel and the single atom
We all have times we wish we could go back in time and make a different decision. Now that appears to be possible – for single atoms, at least. Physicists at the Australian National University have co...
Scientists Have Discovered A New State Of Matter, Called 'Jahn-Teller Metals'
An international team of scientists has announced the discovery of a new state of matter in a material that appears to be an insulator, superconductor, metal and magnet all rolled into one, saying tha...
"Quantum Mechanics and the Structure of Atoms"
Find out what Quantum Mechanics is!
Atomic theory
In chemistry and physics, atomic theory is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms. It began as a philosophical concept in anci...
Atomic theory - Wikipedia
Atomism
Atomism (from Greek ἄτομον, atomon, i.e. "uncuttable", "indivisible") is a natural philosophy that developed in several ancient traditions. The atomists theorized that nature consists of two fundament...
Atomic physics
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus andth...
Mass number
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It determines the atomic mass of...
Atomic mass
The atomic mass (ma) is the mass of an atomic particle, sub-atomic particle, or molecule. The protons and neutrons account for almost all of the mass of an atom. It is commonly expressed in unified at...
Atomic radius
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding cloud of electrons...
Atomic radius - Wikipedia
Atomic orbital
An atomic orbital is a mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom. This function can be used to calculate the probability of f...
Atomic orbital - Wikipedia
Electron configuration
In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, ...
Electron configuration - Wikipedia
Energy level
A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy. This contrasts with classical particles, which can have any ener...
Energy level - Wikipedia
Atomic spectral line
Spectroscopy /spɛkˈtrɒskəpi/ is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wav...
Atomic spectral line - Wikipedia
Electron magnetic dipole moment
In atomic physics, the electron magnetic moment, or more specifically the electron magnetic dipole moment, is the magnetic moment of an electron caused by its intrinsic properties of spin and electric...
Electron magnetic dipole moment - Wikipedia
Spectroscopy
Spectroscopy /spɛkˈtrɒskəpi/ is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wav...
Spectroscopy - Wikipedia
Subatomic particle
In the physical sciences, subatomic particles are particles much smaller than atoms. There are two types of subatomic particles: elementary particles, which according to current theories are not made ...
Atomic nucleus
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911 as a result of Ernest Rutherford's interpretation of the 1909 Geiger–Marsden...
Atomic nucleus - Wikipedia