Structure and bonding of [Pd 2 Sn 18 ] 4− : an interesting example of the mutual delocalisation phenomenon

The [Pd 2 Sn 18 ] 4− cluster can be elucidated based on the mutual delocalisation of two identical [PdSn 9 ] 2− fragments. Other roles of the [E 9 ] 2− (E = Group 14 element) fragments were also examined.