منابع مشابه
Moro , Ferroelectricity in Free Niobium Clusters
www.sciencemag.org (this information is current as of July 30, 2007 ): The following resources related to this article are available online at http://www.sciencemag.org/cgi/content/full/300/5623/1265 version of this article at: including high-resolution figures, can be found in the online Updated information and services, http://www.sciencemag.org/cgi/content/full/300/5623/1265/DC1 can be found...
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Cryogenic molecular beam experiments show that the ferroelectric dipole moments of small niobium clusters with an even number of valence electrons n are typically greater than those with odd n. This is verified in alloy clusters NbNXM where X = Al, Au, O, Mn, Fe, and Co; N ≤ 100;M ≤ 3. Like in superconducting alloys, Mn doping quenches the effect while Al and Au enhance it, suggesting a relatio...
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Surprisingly large, spontaneous electric dipole moments recently observed in homonuclear niobium clusters below 100 K are explained using first-principles electronic structure calculations. The calculated moments for Nb(n) (n < or =15) generally agree with the experimental data. A strong correlation is found between the geometrical asymmetry of the cluster and electric dipole: its magnitude is ...
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ژورنال
عنوان ژورنال: Science
سال: 2003
ISSN: 0036-8075,1095-9203
DOI: 10.1126/science.1083247