Metal clusters NICS values

Calculated NICS values suggest their aromatic behavior which is reflected through their additional stability often rationalized via a shell filling model. Both AlyC" and AlyO" are stable species relative to their neighbours formed by changing the number of electrons and/or the number of A1 atoms Original cluster unit of Al7C is more or less remain undisturbed when it forms compounds with alkali metals. 

Exclusively ir-aromatic metal clusterslike X X=Bq, Mg, Ca, NaX, Na2 3, Y Y= Zn, Cd, Hg, Be, Mg, Ca have also been studied. The NICS(O) value for Ca3 is positive whereas its NICS(l) value is negative. Some of them exhibit bond stretch isomerism . Trigonal dianion aromatic metal clusters " " " like Y F=Be, Mg, Ca containing two TT-electrons can replace the cyclopentadienyl rings to form various metallocene analogues (Fig. 17 and 18) and multidecker sandwich complexes They can stabilize a direct Zn-Zn bond and can trap hydrogen molecules. ... 

The NICS Values of the All-Metal Cluster When They Form H-Bonded Complex with HF and When are Isolated Units... 

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