Structure and bonding of [Pd2Sn18]4-: an interesting example of the mutual delocalisation phenomenon

In this article, we have presented a computational analysis on the structure and bonding of [Pd2Sn18](4-)and illustrated that it serves as an interesting example of OMO-UMO mutual delocalisation with two identical [PdE9](2-) fragments. We have also illustrated the alternative roles that could be played by an [ME9](2-)/[E-9](2-) fragment, a simple L-type donor and a lone-pair acceptor.