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Title: Experimental and theoretical evidence of attractive interactions between dianions: [PdCl 4 ] 2− ⋯[PdCl 4 ] 2−
Inspection of the arrangement of tetrachloridopalladate( ii ) centers in a crystalline solid places the Cl of one [PdCl 4 ] 2− directly above the Pd center of its neighbor. A survey of the CSD provides 22 more examples of such MX 4 2− ⋯MX 4 2− complexes, with M being a Group 10 metal and X = Cl, Br, or I. Quantum calculations attribute this arrangement to a π-hole bond wherein Cl lone pairs of one unit transfer charge to vacant orbitals above the Pd center of its neighbor. The stabilizing effect of this bond must overcome the strong Coulombic repulsion between the two dianions, which is facilitated by a polarizable environment as would be present in a crystal, but much more so when the effects of the neighboring counterions are factored in. These conclusions are extended to other [MX 4 ] 2− homodimers, where M represents other members of Group 10, namely Ni and Pt.  more » « less
Award ID(s):
1954310
NSF-PAR ID:
10326175
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Communications
Volume:
57
Issue:
98
ISSN:
1359-7345
Page Range / eLocation ID:
13305 to 13308
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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