We introduce the concept of electrophobic interaction, analogous to hydrophobic interaction, for describing the behavior of impurity atoms in a metal, a “solvent of electrons”. We demonstrate that there exists a form of electrophobic interaction between impurities with closed electron shell structure, which governs their dissolution behavior in a metal. Using He, Be and Ar as examples, we predict by first-principles calculations that the electrophobic interaction drives He, Be or Ar to form a close-packed cluster with a clustering energy that follows a universal power-law scaling with the number of atoms (N) dissolved in a free electron gas, as well as W or Al lattice, as Ec ∝ (N2/3−N). This new concept unifies the explanation for a series of experimental observations of close-packed inert-gas bubble formation in metals, and significantly advances our fundamental understanding and capacity to predict the solute behavior of impurities in metals, a useful contribution to be considered in future material design of metals for nuclear, metallurgical, and energy applications.
Bibliographical noteFunding Information:
This research is supported by the National Magnetic Confinement Fusion Program with Grant No. 2013GB109002 , the National Natural Science Foundation of China with Grant No. 11405006 , and the China Scholarship Council with Grant No. 201506025054 . G.H. Lu acknowledges the financial support from the National Natural Science Foundation of China for Distinguished Young Scientists through Grant No. 51325103 . J.A. Aguiar acknowledges support in part by Oak Ridge National Laboratory's Center User Facility , which is sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy . F. Liu acknowledges the financial support from DOE-BES (No. DE-FG02-04ER46148 ).
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- Electrophobic interaction
- Impurity clustering