Por favor, use este identificador para citar o enlazar este ítem:https://uvadoc.uva.es/handle/10324/76152
Título
Columnar mesomorphism in molecular alloys based on Halogen-Bridged PtII/PtIV mixed valence complexes. The key role of the PtII/PtIV ratio
Año del Documento
2025
Editorial
Elsevier
Descripción
Producción Científica
Documento Fuente
Journal of Molecular Liquids, 2025, vol. 431, p.127663
Resumo
In this paper, we studied the thermotropic behavior and phase diagrams of blends of two platinum-based met-
allomesogens with different oxidation states and ligands, which are prone to self-association through the for-
mation of a mixed-valence system via PtII⋅⋅⋅Cl-PtIV interactions. The constituent molecules are cis-[PtCl2(CNL)2]
(CNL = 2-(6-(4-isocyanophenoxy)hexyloxy)-3,6,7,10,11-pentakisdodecyloxytriphenylene) and [PtCl4(Bipy)]
(Bipy = didodecyl 2,2′-bipyridyl-4,4′-dicarboxylate), which display an organic/inorganic segregated multi-
columnar mesophase and a lamellar mesomorphism, respectively. Firstly, the phase diagram was constructed
using polarized optical microscopy, differential scanning calorimetry and X-ray scattering data. The results
indicated that compositions exceeding 50 % of [PtCl2(CNL)2] led to columnar mesophases very similar to the one
of pure [PtCl2(CNL)2], where triphenylene cores and platinum moieties are segregated into different columnar
units. Then, employing tight-binding quantum chemical methods, we studied the supramolecular organization in
the columnar mesophases, as well as the electronic structure properties of mixtures with compositions larger than
50 % of [PtCl2(CNL)2]. The results revealed that the formation of the metal–organic columns relies on a fine
balance between PtII⋅⋅⋅PtII and PtII⋅⋅⋅Cl-PtIV intermolecular interactions, which strongly depend on the compo-
sition of the system. A deep analysis of the density of states showed that lower concentrations of [PtCl4(Bipy)]
result in a hole-doped system, while at higher [PtCl4(Bipy)] concentrations the intervalence charge transfer
between the metal center in different oxidation states significantly changes the electronic structure.
Materias Unesco
23 Química
Palabras Clave
Metallomesogens
Triphenylene based liquid-crystals
Mixed-Valence Complexes
Molecullar Alloys
Quantum chemical calculation
ISSN
0167-7322
Revisión por pares
SI
Version del Editor
Propietario de los Derechos
© 2025 The Author(s)
Idioma
eng
Tipo de versión
info:eu-repo/semantics/publishedVersion
Derechos
openAccess
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