663 citations · 1k across the 28 of their papers we have counts for
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Colossal Dielectric Permittivity and Superparaelectricity in phenyl pyrimidine based liquid crystals
Yuri P. Panarin, Wanhe Jiang, Neelam Yadav +6
A set of polar rod-shaped liquid crystalline molecules with large dipole moments (mu > 10.4-14.8 D), their molecular structures based on the ferroelectric nematic prototype DIO, ar…
Calorimetric evidence for the existence of an intermediate phase between the ferroelectric nematic phase and the nematic phase in the liquid crystal RM734
Jan Thoen, George Cordoyiannis, Eva Korblova +5
The idea that rod-like molecules possessing an electric dipole moment could exhibit a ferroelectric nematic phase was suggested more than a century ago. However, only recently such…
Dipole-dipole correlations in the nematic phases of symmetric cyanobiphenyl dimers and their binary mixtures with 5CB
Evangelia E. Zavvou, Efthymia Ramou, Ziauddin Ahmed +4
We report on the temperature dependence of birefringence and of the static dielectric permittivity tensor in a series of binary mixtures between the symmetric, bent-shaped, 1",9"-b…
Phase transitions study of the liquid crystal DIO with a ferroelectric nematic, a nematic and an intermediate phase and of mixtures with the ferroelectric nematic compound RM734 by adiabatic scanning calorimetry
Jan Thoen, George Cordoyiannis, Wanhe Jiang +2
Adiabatic scanning calorimetry (ASC) is capable of providing simultaneously the specific enthalpy h(T) and the specific heat capacity cp(T), and is an important tool to determine t…
Study of the experimental and simulated vibrational spectra together with conformational analysis for thioether cyanobiphenyl-based liquid crystal dimers
Barbara Loska, Antoni Kocot, Yuki Arakawa +2
Infrared spectroscopy (IR) and quantum chemistry calculations that are based on the density functional theory (DFT) have been used to study the structure, molecular interactions of…
Increased intermolecular interactions and cluster formation at the onset of the twist-bend nematic phase in thioether cyanobiphenyl-based liquid crystal dimers
Katarzyna Merkel, Barbara Loska, Yuki Arakawa +3
Infrared spectroscopy (IR) and quantum chemistry calculations, based on density functional theory (DFT) were used to study the structure and the molecular interactions in the nemat…
Polar nature of the ferro-electric nematic studied by dielectric spectroscopy
Neelam Yadav, Yuri P. Panarin, Jagdish K. Vij +2
The nematic-nematic transitions in a nematic compound DIO are studied in homogeneously planar and homeotropic aligned cells using dielectric spectroscopy in the frequency range 0.1…
Detection of chiral domains and linear electro-optical response in planar-aligned cells of an achiral rod-like ferro-electric nematic liquid crystal
Neelam Yadav, Yuri P. Panarin, Jagdish K. Vij +2
Chiral domains of opposite chirality are observed surprisingly in a nematic phase of an achiral rod-like liquid crystalline mesogen that shows ferroelectric nematic and antiferroel…
The interplay between spatial and heliconical bond order in twist-bend nematic materials
Rony Saha, Chenrun Feng, Chris Welch +6
The nanostructure of two novel sulfur containing dimer materials has been investigated experimentally by hard and by resonant tender X-ray scattering techniques. On cooling the dim…
Molecular biaxiality determines the helical structure -- Infrared measurements of the molecular order in the NTB phase of difluoro terphenyl dimers
Katarzyna Merkel, Barbara Loska, Chris Welch +2
IR polarized spectroscopy was employed, to obtain the three components of IR absorbance for a series DTC5Cn (n=5,7,9,11) of bent-shaped dimers containing double fluorinated terphen…
Temperature dependence of bend elastic constant in oblique helicoidal cholesterics
Olena S. Iadlovska, Greta Babakhanova, Georg H. Mehl +7
Elastic moduli of liquid crystals, known as Frank constants, are of quintessential importance for understanding fundamental properties of these materials and for the design of thei…
Identification of New Assembly Mode in the Heliconical Nematic Phase via Tender Resonant X-ray Scattering
Yu Cao, Jun Feng, Asritha Nallapaneni +5
Helical structures are exciting and are utilized in numerous applications ranging from biotechnology to displays to medicine. Accurate description and understanding of resonance ef…
Tuning selective reflection of light by surface anchoring in cholesteric cells with oblique helicoidal structures
Olena S. Iadlovska, Graham R. Maxwell, Greta Babakhanova +4
Selective reflection of light by oblique helicoidal cholesteric (ChOH) can be tuned in a very broad spectral range by an applied electric field. In this work, we demonstrate that t…
Characterization of the sub-micrometer hierarchy levels in the twist-bend nematic phase with nanometric helices via photopolymerization. Explanation for the sign reversal in the polar response
Vitaly P. Panov, Sithara P. Sreenilayam, Yuri P. Panarin +3
Photo-polymerization of a reactive mesogen mixed with a mesogenic dimer, shown to exhibit the twist-bend nematic phase (), reveals the complex structure of the self-deforma…
Molecular organization in the twist-bend nematic phase by resonant X-ray scattering at the Se K-edge and by SAXS, WAXS and GIXRD
W. D. Stevenson, Z. Ahmed, X. B. Zeng +3
Using a novel Se-labelled dimer mixed with DTC5C7 aligned by magnetic field, the twist-bend nematic phase (Ntb) in dimers was studied by hard X-ray resonant scattering and by small…
Comparative analysis of anisotropic material properties of uniaxial nematics formed by flexible dimers and rod-like monomers
Greta Cukrov, Youssef Mosaddeghian Golestani, Jie Xiang +5
We report temperature dependencies of material properties such as dielectric anisotropy, birefringence, splay (K11), twist (K22), and bend (K33) elastic constants of the uniaxial n…
Light scattering study of the "pseudo-layer" compression elastic constant in a twist-bend nematic liquid crystal
Z. Parsouzi, Shokir A. Pardaev, C. Welch +9
The nematic twist-bend (TB) phase, exhibited by certain achiral thermotropic liquid crystalline (LC) dimers, features a nanometer-scale, heliconical rotation of the average molecul…
Second harmonic light scattering induced by defects in the twist-bend nematic phase of liquid crystal dimers
Shokir A. Pardaev, S. M. Shamid, M. G. Tamba +8
The nematic twist-bend () phase, exhibited by certain thermotropic liquid crystalline (LC) dimers, represents a new orientationally ordered mesophase -- the first…
Anomalous increase in nematic-isotropic transition temperature in dimer molecules induced by magnetic field
S. M. Salili, M. G. Tamba, S. N. Sprunt +4
We have determined the nematic-isotropic transition temperature as a function of applied magnetic field in three different thermotropic liquid crystalline dimers. These molecules a…
The Design and Investigation of the Self-Assembly of Dimers with two Nematic Phases
Z. Ahmed, C. Welch, G. H. Mehl
A series of non-symmetric dimers were synthesised containing either cyanobiphenyl or difluoroterphenyl moieties on one side and a range of long, short, bent, polar or apolar mesoge…
Hierarchy of Periodic patterns in the twist-bend nematic phase of mesogenic dimers
Vitaly P. Panov, Michael C. M. Varney, Ivan I. Smalyukh +3
Several attractive properties of hydrocarbon-linked mesogenic dimers have been discovered, a major feature of these has been the ability of dimers under confinement to form periodi…
Do the short helices exist in the nematic TB phase?
Ewa Gorecka, Miroslaw Salamonczyk, Anna Zep +4
Dimeric compounds forming twist-bend nematic, Ntb, phase show unusual optical texture related to the formation of arrays of focal conic defects. Some of the focal conics show submi…
On the structure of the Nx phase of symmetric dimers
Anke Hoffmann, Alexandros G. Vanakaras, Alexandra Kohlmeier +2
NMR measurements on a selectively deuteriated liquid crystal dimer CB-C9-CB exhibiting two nematic phases show that the molecules in the lower temperature nematic phase, Nx, experi…
Surface Alignment, Anchoring Transitions, Optical Properties, and Topological Defects in the Thermotropic Nematic Phase of an Organo-Siloxane Tetrapodes
Young-Ki Kim, Bohdan Senyuk, Sung-Tae Shin +3
We perform optical, surface anchoring, and textural studies of an organo-siloxane tetrapode material in the broad temperature range of the nematic phase. The optical, structural, a…