Structural and relativistic

The effects of the lanthanide/actinide contraction on the post-lanthanide/actinide main group elements have been investigated by Bagus et al. and Seth et al., respectively. The latter show that the interpretation of the observed total effect in terms of shell-structure and relativistic effects is dependent on the order in which these contributions are taken into account, i.e., a nonadditive behavior is observed (Figure 6). 

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