Liquid crystalline phthalocyanine spun films for organic vapour sensing

Vapour sensing properties of spin-coated films of mesogenic octa-substituted phthalocyanine derivatives MPcR8, where M = Ni(II), R = –S(CH2)11CH3, –SCH(CH2OC12H25)2, –S(CH2CH2O)3CH3 were investigated using spectroscopic ellipsometry, Raman spectroscopy and surface plasmon resonance (SPR) technique. Solvent molecules with saturated CC bonds such as chloroform are found to have formed hydrogen bonds with alkyl chains of the substituents of phthalocyanine molecules. The sensor response to aromatic compounds such as benzene is, on the other hand, believed to be the consequence of their π–π interaction with the conjugated phthalocyanine ring.