A Branch of Zintl Chemistry: Metal Clusters of Group 15 Elements

Zintl clusters of group 15, characterized by fruitful structures and fascinating bonding patterns, play a special role in Zintl chemistry. This chapter presents some representative Zintl-type clusters containing group 15 elements, including their syntheses, structural characterizations, and bonding analyses. It applies the concept of aromaticity to metalloid and metal cluster systems, which allowed a more comprehensive understanding of the stability of some Zintl-type clusters and aroused extensive interest among chemists. The chapter highlights some clusters involving aromaticity and anti-aromaticity. Most mixed clusters consisting of group 15 elements and transition metals were synthesized from homoatomic Zintl anions. Arsenic resides in the midway position of the pnictogen family, combining the properties of both the nonmetallic and metallic members of group 15 and conferred by this position, the range of its bond energies lies in an intriguing situation.