PUMA publications for /tag/elechttps://puma.ub.uni-stuttgart.de/tag/elecPUMA RSS feed for /tag/elec2024-03-28T22:42:58+01:00Electrochemistry and spectroelectrochemistry (EPR, UV-visible-near-IR) of platinum(II) 2,2'-bipyridine and ring-metalated bipyridine complexes: PtII(L-) and PtI(L-) but not PtI(L)https://puma.ub.uni-stuttgart.de/bibtex/2c59a9add849f1cb3755ec89db78d6ba1/huebleriachuebleriac2022-06-15T11:26:56+02:00ESR;platinum UV bipyridine complex dimethylbipyridine elec electrochem electroredn;dimethylaminobipyridine phenathroline platinum potential;redn pyridine redox reversible spectrum;diaminoethane <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Paul S. Braterman" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/0"><span itemprop="name">P. Braterman</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Jae Inh Song" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/1"><span itemprop="name">J. Song</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Franz M. Wimmer" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/2"><span itemprop="name">F. Wimmer</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Smita Wimmer" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/3"><span itemprop="name">S. Wimmer</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang Kaim" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/4"><span itemprop="name">W. Kaim</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Axel Klein" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/5"><span itemprop="name">A. Klein</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="R. D. Peacock" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/6"><span itemprop="name">R. Peacock</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Inorganic Chemistry</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">31 </span></span>(<span itemprop="issueNumber">24</span>):
<span itemprop="pagination">5084--5088</span></em> </span>(<em><span>1992<meta content="1992" itemprop="datePublished"/></span></em>)</span>Wed Jun 15 11:26:56 CEST 2022Inorganic Chemistry245084--5088Electrochemistry and spectroelectrochemistry (EPR, UV-visible-near-IR) of platinum(II) 2,2'-bipyridine and ring-metalated bipyridine complexes: PtII(L-) and PtI(L-) but not PtI(L)311992ESR;platinum UV bipyridine complex dimethylbipyridine elec electrochem electroredn;dimethylaminobipyridine phenathroline platinum potential;redn pyridine redox reversible spectrum;diaminoethane The Pt(II) complexes [Pt(bpy)(py)2]2+, [Pt(bpy)(Me2N-py)2]2+, [Pt(Me2-bpy)(py)2]2+, [Pt(bpy)(en)]2+, [Pt(Mebpy - H)(py)2]2+, [Pt(Mebpy - H)(bpy)]2+ (VI), [Pt(phen)(py)2]2+, and [Pt(py)4]2+ (VIII) (bpy, 2,2'-bipyridine; py, pyridine; Mebpy - H, N-methyl-2,2'-bipyridinium-3-yl-C,N'; Me2-bpy, 4,4'-dimethyl-2,2'-bipyridine; Me2N-py, 4-(dimethylamino)pyridine; en, 1,2-diaminoethane; phen, 1,10-phenanthroline) have been investigated by cyclic voltammetry and where possible by EPR spectroelectrochem. and by UV-vis-near-IR spectroelectrochem. All complexes except VIII show at least two reversible reductive one-electron processes; VI shows three, and VIII shows one chem. irreversible process. In all cases, the doubly reduced species showed the characteristic \textgreek{p}* $\rightarrow$ \textgreek{p}* UV-visible-near-IR absorptions of the ligand anion radicals. For the singly reduced species, EPR spectra show the added electron to be localized on the bipyridine-type ligand. However, the UV-visible-near-IR spectra of these species are not typical of ligand-based redn. products, and the potentials are less neg. than expected for such a process. It is concluded that the singly reduced species are best formulated as contg. Pt(II), with the semioccupied and/or th lowest unoccupied ligand orbitals (corresponding to the LUMO and SLUMO of the unreduced parent species) being perturbed by the presence of metal orbitals. The doubly reduced species, however, are straightforward anion radical complexes of Pt(I). [on SciFinder(R)]Electron transfer catalyzed substitution in carbonyl complexes. IV. Mononuclear s- and p-coordinated complexes of manganese, chromium and tungsten with tetracyanoethylene and tetracyano-p-quinodimethanehttps://puma.ub.uni-stuttgart.de/bibtex/20cff40fc8107eaab368fd4674d35f897/huebleriachuebleriac2022-06-15T11:26:56+02:00IR TCNQ chromium complex;TCNE elec manganese mechanism metal metal;substitution potential redox solvate tetracyanoethene tungsten <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Barbara Olbrich-Deussner" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/0"><span itemprop="name">B. Olbrich-Deussner</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Renate Gross" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/1"><span itemprop="name">R. Gross</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang. Kaim" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/2"><span itemprop="name">W. Kaim</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Journal of Organometallic Chemistry</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">366 </span></span>(<span itemprop="issueNumber">1-2</span>):
<span itemprop="pagination">155--174</span></em> </span>(<em><span>1989<meta content="1989" itemprop="datePublished"/></span></em>)</span>Wed Jun 15 11:26:56 CEST 2022Journal of Organometallic Chemistry1-2155--174Electron transfer catalyzed substitution in carbonyl complexes. IV. Mononuclear \textgreek{s}- and \textgreek{p}-coordinated complexes of manganese, chromium and tungsten with tetracyanoethylene and tetracyano-p-quinodimethane3661989IR TCNQ chromium complex;TCNE elec manganese mechanism metal metal;substitution potential redox solvate tetracyanoethene tungsten Reactions of the electron-rich solvates (\textgreek{h}5-C5MenH5-n)(CO)2Mn(THF) (n = 5, 1) and (CO)5M(THF) (M = Cr, W) or of the complex (\textgreek{h}6-C6Me6)(CO)2Cr[P(OMe)3] with the strong acceptor ligands tetracyanoethene (TCNE) and tetracyano-p-quinodimethane (TCNQ) yield mononuclear complexes. An electron transfer autocatalytic mechanism is invoked to rationalize the extremely rapid exchange of THF or phosphite by TCNE or TCNQ as compared with conventional substitution reactions of these carbonylmetal species. Varying degrees of electron transfer from the metal fragments to the acceptor ligands are evident from electrochem. studies and from C$\equiv$N, C:C and C:O stretching frequencies as obtained by IR vibrational spectroscopy. IR data also show that the neutral diamagnetic M(CO)5 complexes are \textgreek{p} coordinated whereas the mixed carbonyl/carbocycle contg. metal fragments are bonded in \textgreek{s} fashion via nitrile N centers. A \textgreek{p} $\rightarrow$ \textgreek{s} coordination change has been established ESR-spectroscopically for the one-electron redn. of (TCNE)W(CO)5. [on SciFinder(R)]On the reaction of aromatic phosphanes with electrons. IV. Significance of low-lying orbitals at phosphorus for the mobility and coordinative characteristics of PR2 substituents in reduced p-phenylenediphosphaneshttps://puma.ub.uni-stuttgart.de/bibtex/2bc897626d7bb9b32ec9906cfc70e209c/huebleriachuebleriac2022-06-15T11:26:56+02:00arom elec electrochem orbital;redox oxidn phosphane phosphane;electron phosphorus potential reaction redn transfer <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Renate Gross-Lannert" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/0"><span itemprop="name">R. Gross-Lannert</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang Kaim" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/1"><span itemprop="name">W. Kaim</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Ulrike Lechner" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/2"><span itemprop="name">U. Lechner</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Eberhard Roth" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/3"><span itemprop="name">E. Roth</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Conny. Volger" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/4"><span itemprop="name">C. Volger</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Zeitschrift fuer Anorganische und Allgemeine Chemie</span>, </em> </span>(<em><span>1989<meta content="1989" itemprop="datePublished"/></span></em>)</span>Wed Jun 15 11:26:56 CEST 2022Zeitschrift fuer Anorganische und Allgemeine Chemie47--56On the reaction of aromatic phosphanes with electrons. IV. Significance of low-lying orbitals at phosphorus for the mobility and coordinative characteristics of PR2 substituents in reduced p-phenylenediphosphanes5791989arom elec electrochem orbital;redox oxidn phosphane phosphane;electron phosphorus potential reaction redn transfer Dinuclear complexes of the ligands 1,4-R2P-C6H4-PR2 (R = Me, Ph) with the carbonylmetal fragments (C5H4CH3)Mn(CO)2 and M(CO)5 (M = Cr, Mo, W) were studied by cyclic voltammetry. The dimanganese complex shows reversible oxidn. to ESR-detectable MnII but no detectable splitting of the cyclic voltammetric wave, the p-phenylenediphosphane bridge does apparently not permit effective metal-metal interaction. The free ligands are reversibly reduced to persistent, ESR-detectable anion radicals with hindered rotation of the PR2 substituents. The carbonylmetal complexes, on the other hand, show dissocn. on electron uptake despite their less neg. redn. potentials. This behavior stands in contrast to main-group element complexes of these ligands and is attributed to the competition between the metal carbonyl fragment and the added electron for the low-lying unoccupied orbitals (\textgreek{s}* at P. [on SciFinder(R)]On the reaction of aromatic phosphanes with electrons. IV. Significance of low-lying orbitals at phosphorus for the mobility and coordinative characteristics of PR2 substituents in reduced p-phenylenediphosphaneshttps://puma.ub.uni-stuttgart.de/bibtex/2bc897626d7bb9b32ec9906cfc70e209c/b_schwederskib_schwederski2019-07-15T13:41:23+02:00arom elec electrochem orbital;redox oxidn phosphane phosphane;electron phosphorus potential reaction redn transfer <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Renate Gross-Lannert" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/0"><span itemprop="name">R. Gross-Lannert</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang Kaim" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/1"><span itemprop="name">W. Kaim</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Ulrike Lechner" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/2"><span itemprop="name">U. Lechner</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Eberhard Roth" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/3"><span itemprop="name">E. Roth</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Conny. Volger" itemprop="url" href="/person/15eae7af5c89b929c1b1711a700c12b57/author/4"><span itemprop="name">C. Volger</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Zeitschrift fuer Anorganische und Allgemeine Chemie</span>, </em> </span>(<em><span>1989<meta content="1989" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Zeitschrift fuer Anorganische und Allgemeine Chemie47--56On the reaction of aromatic phosphanes with electrons. IV. Significance of low-lying orbitals at phosphorus for the mobility and coordinative characteristics of PR2 substituents in reduced p-phenylenediphosphanes5791989arom elec electrochem orbital;redox oxidn phosphane phosphane;electron phosphorus potential reaction redn transfer Dinuclear complexes of the ligands 1,4-R2P-C6H4-PR2 (R = Me, Ph) with the carbonylmetal fragments (C5H4CH3)Mn(CO)2 and M(CO)5 (M = Cr, Mo, W) were studied by cyclic voltammetry. The dimanganese complex shows reversible oxidn. to ESR-detectable MnII but no detectable splitting of the cyclic voltammetric wave, the p-phenylenediphosphane bridge does apparently not permit effective metal-metal interaction. The free ligands are reversibly reduced to persistent, ESR-detectable anion radicals with hindered rotation of the PR2 substituents. The carbonylmetal complexes, on the other hand, show dissocn. on electron uptake despite their less neg. redn. potentials. This behavior stands in contrast to main-group element complexes of these ligands and is attributed to the competition between the metal carbonyl fragment and the added electron for the low-lying unoccupied orbitals (\textgreek{s}* at P. [on SciFinder(R)]Electron transfer catalyzed substitution in carbonyl complexes. IV. Mononuclear s- and p-coordinated complexes of manganese, chromium and tungsten with tetracyanoethylene and tetracyano-p-quinodimethanehttps://puma.ub.uni-stuttgart.de/bibtex/20cff40fc8107eaab368fd4674d35f897/b_schwederskib_schwederski2019-07-15T13:41:23+02:00IR TCNQ chromium complex;TCNE elec manganese mechanism metal metal;substitution potential redox solvate tetracyanoethene tungsten <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Barbara Olbrich-Deussner" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/0"><span itemprop="name">B. Olbrich-Deussner</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Renate Gross" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/1"><span itemprop="name">R. Gross</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang. Kaim" itemprop="url" href="/person/105356a17a53bff71e0ff8347650bfbd0/author/2"><span itemprop="name">W. Kaim</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Journal of Organometallic Chemistry</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">366 </span></span>(<span itemprop="issueNumber">1-2</span>):
<span itemprop="pagination">155--174</span></em> </span>(<em><span>1989<meta content="1989" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Journal of Organometallic Chemistry1-2155--174Electron transfer catalyzed substitution in carbonyl complexes. IV. Mononuclear \textgreek{s}- and \textgreek{p}-coordinated complexes of manganese, chromium and tungsten with tetracyanoethylene and tetracyano-p-quinodimethane3661989IR TCNQ chromium complex;TCNE elec manganese mechanism metal metal;substitution potential redox solvate tetracyanoethene tungsten Reactions of the electron-rich solvates (\textgreek{h}5-C5MenH5-n)(CO)2Mn(THF) (n = 5, 1) and (CO)5M(THF) (M = Cr, W) or of the complex (\textgreek{h}6-C6Me6)(CO)2Cr[P(OMe)3] with the strong acceptor ligands tetracyanoethene (TCNE) and tetracyano-p-quinodimethane (TCNQ) yield mononuclear complexes. An electron transfer autocatalytic mechanism is invoked to rationalize the extremely rapid exchange of THF or phosphite by TCNE or TCNQ as compared with conventional substitution reactions of these carbonylmetal species. Varying degrees of electron transfer from the metal fragments to the acceptor ligands are evident from electrochem. studies and from C$\equiv$N, C:C and C:O stretching frequencies as obtained by IR vibrational spectroscopy. IR data also show that the neutral diamagnetic M(CO)5 complexes are \textgreek{p} coordinated whereas the mixed carbonyl/carbocycle contg. metal fragments are bonded in \textgreek{s} fashion via nitrile N centers. A \textgreek{p} $\rightarrow$ \textgreek{s} coordination change has been established ESR-spectroscopically for the one-electron redn. of (TCNE)W(CO)5. [on SciFinder(R)]Electrochemistry and spectroelectrochemistry (EPR, UV-visible-near-IR) of platinum(II) 2,2'-bipyridine and ring-metalated bipyridine complexes: PtII(L-) and PtI(L-) but not PtI(L)https://puma.ub.uni-stuttgart.de/bibtex/2c59a9add849f1cb3755ec89db78d6ba1/b_schwederskib_schwederski2019-07-15T13:41:23+02:00ESR;platinum UV bipyridine complex dimethylbipyridine elec electrochem electroredn;dimethylaminobipyridine phenathroline platinum potential;redn pyridine redox reversible spectrum;diaminoethane <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Paul S. Braterman" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/0"><span itemprop="name">P. Braterman</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Jae Inh Song" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/1"><span itemprop="name">J. Song</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Franz M. Wimmer" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/2"><span itemprop="name">F. Wimmer</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Smita Wimmer" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/3"><span itemprop="name">S. Wimmer</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang Kaim" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/4"><span itemprop="name">W. Kaim</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Axel Klein" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/5"><span itemprop="name">A. Klein</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="R. D. Peacock" itemprop="url" href="/person/1bf525096cdaf00f7b7cf2c0856c0819a/author/6"><span itemprop="name">R. Peacock</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Inorganic Chemistry</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">31 </span></span>(<span itemprop="issueNumber">24</span>):
<span itemprop="pagination">5084--5088</span></em> </span>(<em><span>1992<meta content="1992" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Inorganic Chemistry245084--5088Electrochemistry and spectroelectrochemistry (EPR, UV-visible-near-IR) of platinum(II) 2,2'-bipyridine and ring-metalated bipyridine complexes: PtII(L-) and PtI(L-) but not PtI(L)311992ESR;platinum UV bipyridine complex dimethylbipyridine elec electrochem electroredn;dimethylaminobipyridine phenathroline platinum potential;redn pyridine redox reversible spectrum;diaminoethane The Pt(II) complexes [Pt(bpy)(py)2]2+, [Pt(bpy)(Me2N-py)2]2+, [Pt(Me2-bpy)(py)2]2+, [Pt(bpy)(en)]2+, [Pt(Mebpy - H)(py)2]2+, [Pt(Mebpy - H)(bpy)]2+ (VI), [Pt(phen)(py)2]2+, and [Pt(py)4]2+ (VIII) (bpy, 2,2'-bipyridine; py, pyridine; Mebpy - H, N-methyl-2,2'-bipyridinium-3-yl-C,N'; Me2-bpy, 4,4'-dimethyl-2,2'-bipyridine; Me2N-py, 4-(dimethylamino)pyridine; en, 1,2-diaminoethane; phen, 1,10-phenanthroline) have been investigated by cyclic voltammetry and where possible by EPR spectroelectrochem. and by UV-vis-near-IR spectroelectrochem. All complexes except VIII show at least two reversible reductive one-electron processes; VI shows three, and VIII shows one chem. irreversible process. In all cases, the doubly reduced species showed the characteristic \textgreek{p}* $\rightarrow$ \textgreek{p}* UV-visible-near-IR absorptions of the ligand anion radicals. For the singly reduced species, EPR spectra show the added electron to be localized on the bipyridine-type ligand. However, the UV-visible-near-IR spectra of these species are not typical of ligand-based redn. products, and the potentials are less neg. than expected for such a process. It is concluded that the singly reduced species are best formulated as contg. Pt(II), with the semioccupied and/or th lowest unoccupied ligand orbitals (corresponding to the LUMO and SLUMO of the unreduced parent species) being perturbed by the presence of metal orbitals. The doubly reduced species, however, are straightforward anion radical complexes of Pt(I). [on SciFinder(R)]