TY - JOUR
T1 - Studies of electronic coupling and mixed valency in metal-metal quadruply bonded complexes linked by dicarboxylate and closely related ligands
AU - Chisholm, Malcolm H.
AU - Patmore, Nathan J.
PY - 2007/1/1
Y1 - 2007/1/1
N2 - Complexes of the form [(tBuCO2)3M 2]2(μ-O2C-X-CO2), where M is Mo or W and X is a π conjugated organic group, are ideally suited for studies of electronic coupling between the two redox centers via M2 δ-bridge π conjugation. The complexes have intense metal-to-bridge charge-transfer transitions in the visible or near-IR region of the spectrum and exhibit thermo-, solvato- and electrochromic behavior. Chemical oxidation results in the formation of mixed-valence species that are particularly well-suited for the study of the class II/III border. The extent of electronic coupling is determined by a variety of spectroscopic techniques and, in particular, by EPR and electronic absorption spectroscopy. The latter provides a direct measure of the electronic coupling parameter Hab in pairs (Mo and W) of otherwise identical complexes. Similarly, the substitution within the bridge of the CO2 group by COS or RNCO allows an evaluation of the mechanism of the electronic coupling in closely related complexes. Electronic structure calculations employing density functional theory complement frontier molecular orbital theory in the interpretation of the physicochemical properties of these complexes.
AB - Complexes of the form [(tBuCO2)3M 2]2(μ-O2C-X-CO2), where M is Mo or W and X is a π conjugated organic group, are ideally suited for studies of electronic coupling between the two redox centers via M2 δ-bridge π conjugation. The complexes have intense metal-to-bridge charge-transfer transitions in the visible or near-IR region of the spectrum and exhibit thermo-, solvato- and electrochromic behavior. Chemical oxidation results in the formation of mixed-valence species that are particularly well-suited for the study of the class II/III border. The extent of electronic coupling is determined by a variety of spectroscopic techniques and, in particular, by EPR and electronic absorption spectroscopy. The latter provides a direct measure of the electronic coupling parameter Hab in pairs (Mo and W) of otherwise identical complexes. Similarly, the substitution within the bridge of the CO2 group by COS or RNCO allows an evaluation of the mechanism of the electronic coupling in closely related complexes. Electronic structure calculations employing density functional theory complement frontier molecular orbital theory in the interpretation of the physicochemical properties of these complexes.
UR - http://www.scopus.com/inward/record.url?scp=33846411867&partnerID=8YFLogxK
U2 - 10.1021/ar068100i
DO - 10.1021/ar068100i
M3 - Article
C2 - 17226942
AN - SCOPUS:33846411867
VL - 40
SP - 19
EP - 27
JO - Accounts of Chemical Research
JF - Accounts of Chemical Research
SN - 0001-4842
IS - 1
ER -