Zinc(II) Bisterpyridine Complexes: The Influence of the Cation on the π-Conjugation between Terpyridine and the Lateral Phenyl Substituent
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Presselt, Martin; Dietzek, Benjamin; Schmitt, Michael; J\", ; urgen Popp, ; Winter, Andreas; Chiper, Manuela; Friebe, Christian; Schubert, Ulrich S.
- Abstract:
- The synthesis and photophysical properties of an ethynylphenyl-substituted terpyridine ligand L and its
corresponding zinc(II) complex [Zn(L)2](PF6)2, serving as model compounds for self-assembling Zn(II)-
based metallopolymers suited for photoluminscent and electroluminescent devices, are presented. The UV-vis
spectra are characterized, and the photoluminescence quantum yields are determined. The ground-state structures
are calculated by means of DFT, and the structural key features are approved by experimental as well as by
DFT-calculated Raman spectra. Special attention is paid to the π-electron delocalization between phenylene
(ph) and pyridine (py) and, in particular, to changes in the ph-py bond due to complexation. The DFTcalculated
ph-py bond shortening in [Zn(L)2](PF6)2 compared to L correlates well with the higher wavenumber
of the V(ph-py(trig)) vibration, which involves strong ph-py bond stretching. The higher ellipticity in the
ph-py bond due to complexation, calculated according to Bader’s QTAIM indicating the π-character of a
bond, is confirmed by the higher Raman intensity of the V(ph-py(trig)) vibration. The electron density
distributions in the ph-py bond between [Zn(L)2](PF6)2 and L are compared in an inter-ΔF plot, which
highlights the changes in the bonding situation of the ph-py bond induced by complex forming.
- Year:
- 2008
- Type of Publication:
- Article
- Journal:
- Journal of Physical Chemistry C
- Volume:
- 112
- Pages:
- 18651 - 18660