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2.5 Complex structures
Zintl-phases- overview
Experimental observation:
element 1 + element 2 → compound (liquid ammonia)
element 1: alkali, alkaline-earth, rare-earth metals
element 2 (examples): Ga-Tl, Si-Pb, As-Bi…
Properties of the compounds:
• salt like structures, colored Characteristics of
• soluble clusters in liquid ammonia Zintl phases
• semiconductors
• fixed composition, valence compounds
• The structure of the anions follows the octet rule
The Zintl-rule • The number of bonds of each anion is 8-N
The Zintl-rule
rule“)
( („ „8 8- -N N- -rule“) (N = number of electrons of the anion)
• The anions adopt structures related to the elements
of group N
