A quasi-elastic neutron scattering study of molecular dynamics in columnar liquid crystal

Non-uniformly substituted phthalocyanines and related compounds: alkylated tribenzo-imidazolo[4,5]- porphyrazines

“…The alkoxy groups in particular at the non-peripheral sites lead to a significant bathochromic shift of the Q band [15]. Pcs bearing alkyl groups exhibit interesting discotic mesophase behaviour [16][17][18].…”

Self-assembly and dynamics of liquid crystals

“…The incoherent quasi-elastic neutron scattering (QENS) from the heptyl and octyl derivatives of the acta-alkylphthalocyanines, CnPcH2, in their crystalline and liquid crystalline (discotic columnar) phases was studied aiming at probing the mobility of the alkyl chains [123], A diffusive motion was observed on the 10'10 to 10'12 s time scale that was attributed to alkyl chain dynamics. A major finding in this study was the small discontinuity in the elastic fraction of the quasi-elastic scattering, consistent with a change in the molecular tilt at the transition between the two Dhd phases.…”