Version 1
: Received: 6 May 2019 / Approved: 7 May 2019 / Online: 7 May 2019 (11:19:26 CEST)
Version 2
: Received: 17 May 2019 / Approved: 17 May 2019 / Online: 17 May 2019 (14:12:50 CEST)
Maciá Barber, E. Chemical Bonding and Physical Properties in Quasicrystals and Their Related Approximant Phases: Known Facts and Current Perspectives. Appl. Sci.2019, 9, 2132.
Maciá Barber, E. Chemical Bonding and Physical Properties in Quasicrystals and Their Related Approximant Phases: Known Facts and Current Perspectives. Appl. Sci. 2019, 9, 2132.
Maciá Barber, E. Chemical Bonding and Physical Properties in Quasicrystals and Their Related Approximant Phases: Known Facts and Current Perspectives. Appl. Sci.2019, 9, 2132.
Maciá Barber, E. Chemical Bonding and Physical Properties in Quasicrystals and Their Related Approximant Phases: Known Facts and Current Perspectives. Appl. Sci. 2019, 9, 2132.
Abstract
Quasicrystals are a class of ordered solids made of typical metallic atoms but they do not exhibit the physical properties usually signaling the presence of metallic bonding and their electrical and thermal transport properties resemble a more semiconductor-like than metallic character. In this paper I first review a number of experimental results and numerical simulations suggesting that the origin of the unusual properties of these compounds can be traced back to two main features. For one thing, we have the formation of covalent bonds among certain atoms grouped into clusters at a local scale. Thus, the nature of chemical bonding among certain constituent atoms should play a significant role in the onset of non-metallic physical properties of quasicrystals bearing transition-metal elements. On the other hand, the self-similar symmetry of the underlying structure gives rise to the presence of an extended chemical bonding network due to a hierarchical nesting of clusters. This novel structural design leads to the existence of quite diverse wave functions, whose transmission characteristics range from extended to almost localized ones. Finally, the potential of quasicrystals as thermoelectric materials is discussed on the basis of their specific transport properties.
Keywords
quasicrystals; chemical bond; thermoelectric materials
Subject
Chemistry and Materials Science, Electronic, Optical and Magnetic Materials
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
