The FeIII/FeII vs. Fe22.5 Formulation in Mixed-Valent Species (NC)4Fe(BL)Fe(CN)43-, BL = 2,2'-Bipyrimidine and 3,6-Bis(2-pyridyl)-1,2,4,5-tetrazine. Distance and Size Do Not Always Matter
Two mol.-bridged bis(tetracyanoiron) complexes (NC)4Fe(BL)Fe(CN)4n-, BL = 2,2'-bipyrimidine (bpym) and 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz), were studied by EPR, UV/visible/near-IR and IR spectroelectrochem. (n = 2-5) in aprotic media. Following these results, the Fe22.5 formulation is the correct valence description for the metal centers in the bptz-bridged trianion (Kc = 1014.6 in MeCN), whereas the localized FeIII/FeII formulation is appropriate for the bpym-bridged system (Kc = 105.4 in MeCN and 106.4 in CH2Cl2). In contrast to common perception, the larger tetrazine-bridged system with the longer metal-metal distance exhibits much stronger metal-metal coupling than the bpym-bridged analog, a consequence of the very low lying p* LUMO of tetrazines with high MO coeffs. at the coordinating N centers. on SciFinder(R)
%0 Journal Article
%1 Gloeckle.1999
%A Gloeckle, Markus
%A Kaim, Wolfgang
%A Katz, Nestor E.
%A Posse, Monica Garcia
%A Cutin, Edgardo H.
%A Fiedler, Jan.
%D 1999
%J Inorganic Chemistry
%K bipyrimidine complex complex;iron complex;redn complex;redox complex;spectroelectrochem cyano dinuclear electrochem iron potential prepn;oxidn spectro tetrazinebispyridine
%N 14
%P 3270--3274
%R 10.1021/IC990249L
%T The FeIII/FeII vs. Fe22.5 Formulation in Mixed-Valent Species (NC)4Fe(BL)Fe(CN)43-, BL = 2,2'-Bipyrimidine and 3,6-Bis(2-pyridyl)-1,2,4,5-tetrazine. Distance and Size Do Not Always Matter
%V 38
%X Two mol.-bridged bis(tetracyanoiron) complexes (NC)4Fe(BL)Fe(CN)4n-, BL = 2,2'-bipyrimidine (bpym) and 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz), were studied by EPR, UV/visible/near-IR and IR spectroelectrochem. (n = 2-5) in aprotic media. Following these results, the Fe22.5 formulation is the correct valence description for the metal centers in the bptz-bridged trianion (Kc = 1014.6 in MeCN), whereas the localized FeIII/FeII formulation is appropriate for the bpym-bridged system (Kc = 105.4 in MeCN and 106.4 in CH2Cl2). In contrast to common perception, the larger tetrazine-bridged system with the longer metal-metal distance exhibits much stronger metal-metal coupling than the bpym-bridged analog, a consequence of the very low lying p* LUMO of tetrazines with high MO coeffs. at the coordinating N centers. on SciFinder(R)
@article{Gloeckle.1999,
abstract = {Two mol.-bridged bis(tetracyanoiron) complexes [(NC)4Fe(BL)Fe(CN)4]n-, BL = 2,2'-bipyrimidine (bpym) and 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (bptz), were studied by EPR, UV/visible/near-IR and IR spectroelectrochem. (n = 2-5) in aprotic media. Following these results, the Fe22.5 formulation is the correct valence description for the metal centers in the bptz-bridged trianion (Kc = 1014.6 in MeCN), whereas the localized FeIII/FeII formulation is appropriate for the bpym-bridged system (Kc = 105.4 in MeCN and 106.4 in CH2Cl2). In contrast to common perception, the larger tetrazine-bridged system with the longer metal-metal distance exhibits much stronger metal-metal coupling than the bpym-bridged analog, a consequence of the very low lying \textgreek{p}* LUMO of tetrazines with high MO coeffs. at the coordinating N centers. [on SciFinder(R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Gloeckle, Markus and Kaim, Wolfgang and Katz, Nestor E. and Posse, Monica Garcia and Cutin, Edgardo H. and Fiedler, Jan.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/28e2f987e1e023a3d30198c11e33af518/huebleriac},
doi = {10.1021/IC990249L},
interhash = {f7a3ea637057261ac5828dc4c1737e49},
intrahash = {8e2f987e1e023a3d30198c11e33af518},
issn = {0020-1669},
journal = {Inorganic Chemistry},
keywords = {bipyrimidine complex complex;iron complex;redn complex;redox complex;spectroelectrochem cyano dinuclear electrochem iron potential prepn;oxidn spectro tetrazinebispyridine},
number = 14,
pages = {3270--3274},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {The FeIII/FeII vs. Fe22.5 Formulation in Mixed-Valent Species [(NC)4Fe(BL)Fe(CN)4]3-, BL = 2,2'-Bipyrimidine and 3,6-Bis(2-pyridyl)-1,2,4,5-tetrazine. Distance and Size Do Not Always Matter},
volume = 38,
year = 1999
}