Looking at the Periodic Table of elements, we find about 80 natural/stable isotopes of metals that are nonmagnetic and nonprecious. Among these, the alkali and alkali-earth metals (s-group) are extremely reactive, and the lanthanoids and actinoids (f-group) and some of the d-group metals are of low abundance, leaving roughly 20 elements that can be considered as practical choices for large-scale industrial use in metallic form, especially when talking about nanoparticles. Though each metal has its peculiarities, the basic rules concerning their size-dependent physical properties follow the general trends observed when talking about nanosized structures of other metals. Small crystal size can result in: increased chemical reactivity due to the relatively large number of surface atoms and vacancies at specific crystal edges and apices, melting point depression because of the large surface energy, decreased electrical and
thermal conductivity due to the more pronounced electron and phonon scattering at the crystal boundaries, the appearance of molecular-like electronic states instead of
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