Ring distortions and nano-architecture formed by purpose designed phthalocyanines
Phthalocyanines are a class of compounds intensively studied because of their intense
blue/green colour. The discovery, the synthesis and some of their applications are described
in Chapter 1.
A number of crystal structures have been published in the past. In chapter 2, a comparison
study discusses the effect of the substituents (linear such as n-hexyl or branched such as
iso-pentyl) and the central ion (zinc, nickel, lead and free base) on molecular structure and
packing. Crystal structures have been obtained and a UV-Vis study in solution and in the
solid state as well as Non Linear Optical measurements in solution and in the solid state
have been carried out.
Phthalocyanine arrays containing well-defined scaffolds and support architectures are
currently being investigated for NLO, molecular-electronics and sensor-device applications.
In two different approaches, the synthesis of oligomeric and macromolecular arrays from a
single mono-functionalised phthalocyanine has been investigated. In the first the synthesis
was attempted of a well-defined structure of oligomeric polyisocyanide Pc that should arise
from the synthesis of a peripheral isocyanide-dipeptide substituent which, when
polymerised, should afford a rigid, helical polymeric backbone for the phthalocyanine
array. In the second the synthesis was attempted of a hexameric macromolecular species
affording a defined macromolecular system designed to exhibit properties mediated by both
inter- and intramolecular phthalocyanine interactions. The results are presented together in
Chapter 4 reports the discovery that spin coated films of 1,4,8,11,15,18,22,25-
octakis(hexyl)phthalocyaninato lead (Il) can be used as a medium for the source of Pb2 for
the formation of PbS nanoparticles when exposed to H2S gas. It has been demonstrated that
the formation of CdS nanoparticles can be carried out following the same procedure. The
synthesis and characterisation of CdS and PbS nanoparticles is discussed.