<DIV>I supposed it is the number of valence electrons of the unit cell. Am I right?</DIV>
<DIV> </DIV>
<DIV>[]s,</DIV>
<DIV> </DIV>
<DIV>Roberto</DIV><BR><BR><DIV>
<DIV>
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<P>Blogs: <A href="http://robertoveiga.blogspot.com">http://robertoveiga.blogspot.com</A> e <A href="http://democracialiberal.blogspot.com">http://democracialiberal.blogspot.com</A>.</P></DIV></DIV><p>
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