Premium
XX Through‐Cage Bonding in Cu, Ni, and Cr Complexes with M 3 X 2 Cores (X=S, As)
Author(s) -
Carrasco Rosa,
Aullón Gabriel,
Alvarez Santiago
Publication year - 2009
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200800914
Subject(s) - cage , crystallography , materials science , copper , metallurgy , chemistry , combinatorics , mathematics
Density functional calculations on trinuclear complexes bridged by two sulfur atoms, [(tmeda) 3 Cu 3 (μ‐S) 2 ] 3+ , [(tmeda) 3 Ni 3 (μ‐S) 2 ] 2+ , and [(tmeda) 3 Ni 3 (μ‐S 2 )] 4+ , as well as on the formation of [(tmeda) 3 Cu 3 (μ‐S) 2 ] 3+ from a dinuclear [(tmeda) 2 Cu 2 (μ‐S 2 )] 2+ complex and a mononuclear [(tmeda)Cu(η 2 ‐S 2 )] + fragment, are reported. A qualitative orbital analysis of the M 3 X 2 framework bonding is presented for the case in which each metal atom M has a square planar coordination sphere completed by one bidentate or two monodentate ligands (that is, [(L 2 M) 3 X 2 ] compounds). It is concluded that a framework electron count (FEC) of 12 corresponds to systems with six MX bonds but no XX bond through the cage, while an FEC of 10 favors the formation of an XX bond. Framework electron counting rules are also presented for related M 3 X 2 cores in [(L 5 M) 3 X 2 ] complexes, based on a qualitative molecular orbital (MO) analysis supported by DFT calculations on [(OC) 15 Cr 3 (μ‐As 2 )].