Novel liquid crystals based on fluorinated carbon chains and terminated with SF 5 groups are presented for the first time. Attachment of an SF 5 group separated from a benzylidine group by a fluorinated spacer leads to monotropic nematic and smectic phases, while an enantiotropic nematic phase is observed in mixtures. The phase sequence of these new compounds is comparable to hydrocarbon analogues of nO.m (n-alkoxym-alkylbenzylidine) series. Despite a long alkoxy chain, the nematic f smectic A transition is closer to second order, with M TCP predicted ≈ 0.995 values that are even higher than for the nCB (n-alkylcyanobiphenyls) series. Single crystal and quantum computational studies suggest that electrostatic interactions play a major role in governing the value of M TCP . Molecular packing in the crystal structure exhibits monoclinic P2 1 /a symmetry. A flexible synthetic strategy that allows the synthesis of another homologous series with a bend in the molecular structure is also presented. The bent core structure of 10O.2 SF 5 investigated shows a monotropic, tilted smectic phase for the higher C 10 alkoxy chain. The compounds in this series reveal a high degree of undercooling (well above 50 °C), which is rationalized using finite size effects on nucleation.

Electrochromic effects of antimony doped tin oxide (ATO) nanoparticles are investigated to probe device yellowing (degradation). Voltage vs contrast ratio curves exhibit hysteresis, i.e., image-sticking phenomena due to irreversible charge insertion. X-ray, impedance and optical b* studies suggest that the yellowing/charge trapping is nanoparticle size-dependent with 4 nm size particles exhibiting the least yellowing. Yellowing results in increased impedances of electrode–electrolyte interface and electrode corrosion. Plausible sources of discoloration are formation of insulating complex alkali oxide film, carrier inversion (n-to-p type) through electrochemical Li doping, redeposition of the corroded electrode material and perhaps residual concentration of charge-transfer species.

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