title: Reduced and excited states of (bpym)[PtCl(2)](n)() (bpym = 2,2'-bipyrimidine; n = 1, 2): experiments and DFT calculations.
abstract: The complexes (bpym)PtCl(2) (1) and the new (micro-bpym)[PtCl(2)](2) (2), bpym = 2,2'-bipyrimidine, were synthesized and, in the case of 1, crystallized in solvent-free form for X-ray diffraction. The molecules 1 exhibit two different kinds of stacking motifs in the crystal with an interstack CH--N interaction. Complexes 1 and 2 were found to be sufficiently soluble for cyclic voltammetry, spectroscopy (absorption and emission), and spectroelectrochemical studies (UV-vis, EPR). As a result of single or double coordination of the strongly sigma-accepting [PtCl(2)] fragment to bpym, the paramagnetic anions 1(*)(-)() and 2(*)(-)() and the dianions 1(2-) and 2(2-) could be reversibly generated, despite the presence of metal-halide bonds. DFT calculations of A((195)Pt) and g tensor components confirm that the singly occupied MOs of the monoanionic species have mainly pi(bpym) character with nonnegligible platinum d orbital participation. The assignments of the electronic absorption and emission and resonance Raman spectra for both complexes are supported by DFT calculations.
authors.affiliation: Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany. kaim@iac.uni-stuttgart.de
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kaim
authors.forename: Akbey
authors.initials: A
authors.lastname: Dogan
authors.forename: Matthias
authors.initials: M
authors.lastname: Wanner
authors.forename: Axel
authors.initials: A
authors.lastname: Klein
authors.forename: Ioannis
authors.initials: I
authors.lastname: Tiritiris
authors.forename: Thomas
authors.initials: T
authors.lastname: Schleid
authors.forename: Derk J
authors.initials: DJ
authors.lastname: Stufkens
authors.forename: Theo L
authors.initials: TL
authors.lastname: Snoeck
authors.forename: Eric J L
authors.initials: EJ
authors.lastname: McInnes
authors.forename: Jan
authors.initials: J
authors.lastname: Fiedler
authors.forename: Stanislav
authors.initials: S
authors.lastname: Zális