Computer Sciences
Computer scientists at University of California, Davis, Maynooth University in Ireland and the California Institute of Technology have created DNA molecules that can self-assemble into patterns essentially by running their ...
Mar 20, 2019
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1728
Energy & Green Tech
Batteries power most of our devices, and even some cars. But researchers now report in ACS Applied Materials & Interfaces a step toward running electronic devices in homes and offices on the light coming from lamps scattered ...
Mar 13, 2019
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26
Engineering
Anyone who's seen a gecko will likely know they can climb walls. But these common lizards can also run across water nearly as fast as they can move on solid ground. Yet while we know how geckos scale smooth vertical surfaces ...
Dec 7, 2018
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Engineering
In a new study that one scientist called jaw-dropping, a joint UCLA/Caltech team has shown that it is possible to obtain the structures of small molecules, such as certain hormones and medications, in as little as 30 minutes. ...
Nov 12, 2018
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1
Energy & Green Tech
Researchers at Kanazawa University report in the journal Organic Electronics documents a new method for controlling the orientation of conducting molecules in organic solar cells that results in the enhanced light adsorption ...
Oct 26, 2018
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26
Hi Tech & Innovation
Guzzling, devouring, the words fail to reflect the enormity of it all. Data storage eats up cities' worth of power. Back in March, 3M ran a presentation about data, reminding us there was not going to be anything like a slowing ...
Engineering
A research group from Chalmers University of Technology, Sweden, has made great strides toward the development of a specially designed molecule which can store solar energy for later use. These advances have been presented ...
Oct 3, 2018
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760
Energy & Green Tech
To sustain human civilization in the future, clean energy sources must be harnessed to replace the fossil fuels that are now polluting our atmosphere. Solar and wind energy can supply all the necessary energy. However, storage ...
Jul 23, 2018
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648
Energy & Green Tech
Organic solar cells have the potential to become a source of renewable energy which is inexpensive and fast to roll out and scale up. Physicists at the University of Oxford have explored some of the scientific fundamentals ...
Jul 23, 2018
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0
Hi Tech & Innovation
Boston-based Catalog, a startup company focused on solving the looming data storage crisis, has announced to the press that it has received $9 million in funding from several venture capital firms. The funding will go toward ...
A molecule is defined as a sufficiently stable, electrically neutral group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense. In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules and biomolecules.
In the kinetic theory of gases the term molecule is often used for any gaseous particle regardless of its composition. According to this definition noble gas atoms are considered molecules despite the fact that they are composed of a single non-bonded atom.
A molecule may consist of atoms of a single chemical element, as with oxygen (O2), or of different elements, as with water (H2O). Atoms and complexes connected by non-covalent bonds such as hydrogen bonds or ionic bonds are generally not considered single molecules.
No typical molecule can be defined for ionic crystals (salts) and covalent crystals (network solids), although these are often composed of repeating unit cells that extend either in a plane (such as in graphene) or three-dimensionally (such as in diamond or sodium chloride). The theme of repeated unit-cellular-structure also holds for most condensed phases with metallic bonding. In glasses (solids that exist in a vitreous disordered state), atoms may also be held together by chemical bonds without any definable molecule, but also without any of the regularity of repeating units that characterises crystals.
This text uses material from Wikipedia, licensed under CC BY-SA
