Atomic and Molecular Clusters
نویسنده
چکیده
electronic, magnetic, optical a g g r e g a t e s o f and chemical properties are atoms/molecules C found to be very different containing a few to several from their bulk form and t h o u s a n d s o f depend sensitively on their atoms/molecules. They s i z e , s h a p e a n d h ave ve r y d i f f e r e n t composition. Thus, as has properties from isolated been mentioned above, atoms/molecules or bulk clusters form a class of m a t e r i a l s a n d t h u s materials different from the constitute a new type of b u l k a n d i s o l a t e d material. Clusters have atoms/molecules. Looking been around for a long time at the mass distribution of and are a part of our clusters, some are found to everyday life. For example, be much more abundant AgBr clusters are used in than others. These clusters photography. However, are therefore more stable their scientific study received an impetus rather and are called magic clusters. They act like recently.This has been largely due to their superatoms and can be used as building blocks recently recognized technological potential or basis to form a cluster assembled solid. It is which was first anticipated by the legendary physicist Richard Feynman in 1960 in his famous speech entitled ‘There is plenty of room at the bottom'. In this speech he challenged scientists to develop a new field of study where devices and machines could be constructed from components consisting of small number of atoms.
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