Effects of charge on intra-unit distances

Another interesting observation is the VEC obtained for these oxyhalides. Indeed, a classical VEC = 16 is obtained for the first series, M 2M MgX 70, whereas VEC = 14 for the two other series, M 2M MgXi503 and M MgXi303, the latter value of which is unusual in Mg solid-state chemistry. Theoretical calcu- 

7 Physical properties of discrete M6L18- and M6L14-based compounds 

As no intercluster interactions occur in these compounds, the valence electrons remain localized on the Mg clusters and paramagnetism arises when valence electrons are unpaired (for instance, VEC = 15 or VEC = 23 for M Lis or M6L14 respectively). The M M MeXig series is of particular interest because several situations can be encountered owing to the coexistence of both Me and rare earth ion networks in the same compound  

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