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1H NMR study of molecular order and dynamics in CBC9CB Liquid Crystal (2019)
Journal Article
Aluculesei, A., Cachitas, H., Carvalho, J., Vaca Chavez, F., Figueirinhas, J. L., Sebastião, P. J., …Mehl, G. H. (2019). 1H NMR study of molecular order and dynamics in CBC9CB Liquid Crystal. Physical chemistry chemical physics : PCCP, doi:10.1039/c8cp06868b

Molecular order and dynamics of the CB-C9-CB liquid crystalline dimer exhibiting the nematic (N) and the twist bend nematic (Ntb) phases were investigated by proton NMR spectroscopy, using fields of 0.78T and 7.04T, and relaxometry. The first relaxom... Read More

Proton and Deuterium NMR study of the CBC9CB Dimer System (2019)
Journal Article
Carvalho, J., Cruz, C., Figueirinhas, J. L., Tamba, M., Kohlmeier, A., & Mehl, G. H. (in press). Proton and Deuterium NMR study of the CBC9CB Dimer System. Journal of Physical Chemistry B, doi:10.1021/acs.jpcb.8b11526

Using proton and deuterium NMR spectroscopy , this work provides a description of the molecular order of the mesogenic grops in both the Ntb and the classical nematic phase (N), of the liquid crystal dimer CB-C9CB. The proton NMR data were collected... Read More

The induction of the Ntb phase in mixtures (2018)
Journal Article
Ramou, E., Welch, C., Hussey, J., Ahmed, Z., Karahaliou, P. K., & Mehl, G. H. (2018). The induction of the Ntb phase in mixtures. Liquid crystals, 45(13-15), 1929-1935. doi:10.1080/02678292.2018.1524523

We report the induction of the Ntb phase over a wide temperature and concentration range in a binary system. This was achieved by addition of a flexible dopant without LC properties to a flexible dimer exhibiting only a nematic LC phase. The Ntb phas... Read More

Lyotropic ‘hairy’ TiO2 nanorods (2018)
Journal Article
Cheng, F., Verrelli, E., Alharthi, F. A., Kelly, S. M., O'Neill, M., Kemp, N. T., …Anthopoulos, T. (2019). Lyotropic ‘hairy’ TiO2 nanorods. Nanoscale advances, 1, 254-264. doi:10.1039/c8na00054a

We report the synthesis of the first stable, solution-processable and photocrosslinkable hybrid organic/inorganic titanium dioxide nanorods as ‘hairy rods’ coated with phosphonate ligands with photoreactive coumarin groups located in a terminal posit... Read More

Supramolecular organization of liquid-crystal dimers-bis-cyanobiphenyl alkanes on HOPG by scanning tunneling microscopy (2018)
Journal Article
Krzyzewska, K., Jaroch, T., Maranda-Niedbała, A., Pociecha, D., Górecka, E., Ahmed, Z., …Nowakowski, R. (2018). Supramolecular organization of liquid-crystal dimers-bis-cyanobiphenyl alkanes on HOPG by scanning tunneling microscopy. Nanoscale, 10(34), 16201-16210. doi:10.1039/c8nr02069h

2D supramolecular organization of a series of six cyanobiphenyl bimesogens deposited on highly oriented pyrolytic graphite (HOPG) is studied by scanning tunneling microscopy (STM). The adsorbates are 1,ω-bis(4-cyanobiphenyl-4’-yl)alkanes (CBnCB) with... Read More

EPR study of the polydomain structure of the twist-bend nematic phase of CB9CB in the bulk (2018)
Journal Article
Bacchiocchi, C., Tamba, M., Mehl, G. H., Arcioni, A., Miglioli, I., & Zannoni, C. (2018). EPR study of the polydomain structure of the twist-bend nematic phase of CB9CB in the bulk. Liquid crystals, 45(13-15), 2109-2120. doi:10.1080/02678292.2018.1501110

EPR spin probe spectra of the liquid crystal phases exhibited, in the bulk, by the 1″,9″-bis(4- cyanobiphenyl-4’-yl)nonane (CB9CB) bent-shape dimer showed that, on cooling from the isotropic phase, this material forms a uniaxial nematic phase with a... Read More

Characterization of large tilt-angle flexoelectro-optic switching in chiral nematic liquid crystal devices (2018)
Journal Article
Wang, X., Fells, J. A. J., Welch, C., Tamba, M., Mehl, G. H., Morris, S. M., & Elston, S. J. (2018). Characterization of large tilt-angle flexoelectro-optic switching in chiral nematic liquid crystal devices. Liquid crystals, 1-7. doi:10.1080/02678292.2018.1502822

The “flexoelastic ratio”, which is the ratio of the effective flexoelectric coefficient to the elastic coefficients, is commonly used to characterize the electro-optic behavior of chiral nematic liquid crystal (LC) devices that exhibit flexoelectro-o... Read More

Twist-bend nematic phase in cyanobiphenyls and difluoroterphenyls bimesogens (2016)
Journal Article
Panov, V. P., Vij, J. K., & Mehl, G. H. (2017). Twist-bend nematic phase in cyanobiphenyls and difluoroterphenyls bimesogens. Liquid crystals, 44(1), (147-159). doi:10.1080/02678292.2016.1254289. ISSN 0267-8292

The paper reviews assignment of the low-temperature nematic phase observed in simple bimesogenic or dimeric systems based on cyanobiphenyls and difluoroterphenyls to the twist-bend nematic phase, NTB, using a range of experimental techniques. These i... Read More

Director configuration in the twist-bend nematic phase of CB11CB (2016)
Journal Article
Miglioli, I., Bacchiocchi, C., Arcioni, A., Kohlmeier, A., Mehl, G. H., & Zannoni, C. (2016). Director configuration in the twist-bend nematic phase of CB11CB. Journal of materials chemistry. publ. by The Royal Society of Chemistry. C, Materials for optical and electronic devices /, 4(41), (9887-9896). doi:10.1039/c6tc03246j. ISSN 2050-7526

The director distribution in the nematic phases exhibited by the 100,1100-bis(4-cyanobiphenyl-40-yl)undecane (CB11CB) liquid crystal has been studied in the bulk with the EPR spin probe technique. EPR spectra confirmed the presence of an higher tempe... Read More

Fluctuation modes of a twist-bend nematic liquid crystal (2016)
Journal Article
Parsouzi, Z., Shamid, S. M., Borshch, V., Challa, P. K., Baldwin, A. R., Tamba, M. G., …Sprunt, S. (2016). Fluctuation modes of a twist-bend nematic liquid crystal. Physical Review X, 6(2), 021041-1-021041-16. doi:10.1103/PhysRevX.6.021041

We report a dynamic light-scattering study of the fluctuation modes in a thermotropic liquid crystalline mixture of monomer and dimer compounds that exhibits the twist-bend nematic (NTB) phase. The results reveal a spectrum of overdamped fluctuations... Read More