PUMA publications for /bibtexkey/Hasenzahl.1995/b_schwederskihttps://puma.ub.uni-stuttgart.de/bibtexkey/Hasenzahl.1995/b_schwederskiPUMA RSS feed for /bibtexkey/Hasenzahl.1995/b_schwederski2024-03-29T08:05:01+01:00A tale of two complexes, PtMen(RN=CHCH=NR) (n = 2 and n = 4, R = cyclohexyl): Why do PtII and PtIV complexes exhibit virtually identical redox behavior and colors?https://puma.ub.uni-stuttgart.de/bibtex/2ce94821ca575e75325abdaf074d400d3/b_schwederskib_schwederski2019-07-15T13:41:23+02:00charge complex complex;EPR complex;MO complex;crystal complex;electrochem complex;mol complex;platinum diazabutadiene methyl platinum prepn property structure transfer <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Steffen Hasenzahl" itemprop="url" href="/person/19b9041b7f8e5e7875d680d7469561b6d/author/0"><span itemprop="name">S. Hasenzahl</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Hans-Dieter Hausen" itemprop="url" href="/person/19b9041b7f8e5e7875d680d7469561b6d/author/1"><span itemprop="name">H. Hausen</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang. Kaim" itemprop="url" href="/person/19b9041b7f8e5e7875d680d7469561b6d/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">Chemistry - A European Journal</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">1 </span></span>(<span itemprop="issueNumber">1</span>):
<span itemprop="pagination">95--99</span></em> </span>(<em><span>1995<meta content="1995" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Chemistry - A European Journal195--99A tale of two complexes, [PtMen(RN=CHCH=NR)] (n = 2 and n = 4, R = cyclohexyl): Why do PtII and PtIV complexes exhibit virtually identical redox behavior and colors?11995charge complex complex;EPR complex;MO complex;crystal complex;electrochem complex;mol complex;platinum diazabutadiene methyl platinum prepn property structure transfer In spite of their similar cyclic voltammograms, absorption spectra, and solvatochromic behavior, the two 1,4-diazabutadiene title complexes exhibit markedly different photoreactivities and underlying electronic structures, as evident from absorption and EPR spectra of the persistent anion radical forms. The lowest excited state of the nonphotoreactive PtII system [(CyN=CHCH=NCy)PtMe2] has MLCT (metal-to-ligand charge-transfer, 5d $\rightarrow$ \textgreek{p}*) character, and the EPR spectrum of the corresponding anion radical at 〈g〉 = 2.016 exhibits sizable metal/ligand orbital mixing. However, the structurally characterized PtIV complex [(CyN=CHCH=NCy)PtMe4] (C2/c; a 2021.6(2), b 805.3(1), c 1254.2(1) pm; \textgreek{b} 111.05(1)°; V = 1905.7(4) $\times$ 106 pm3; Z = 4) has a low-lying photoreactive LLCT (ligand-to-ligand and charge-transfer, \textgreek{s}Pt-C $\rightarrow$ \textgreek{p}*) excited state in which the axial Pt-C bonds are activated, as already suggested by the longer Pt-C(ax) bonds (214.0(8) pm) relative to Pt-C(eq) in the ground state (204.5(5) pm). The anion radical of the PtIV complex has lost the long-wavelength absorption band in the visible; it shows a well-resolved EPR spectrum at 〈g〉 = 1.9945 with \textgreek{p}-ligand and 195Pt hyperfine structure and a small g anisotropy. A qual. MO scheme is presented to account for the similar frontier-orbital energy differences despite dissimilar underlying electronic structures. [on SciFinder(R)]