A5062475969- Liquid Crystal Research Advancements
- Molecular spectroscopy and chirality
- Surfactants and Colloidal Systems
- Magnetic Properties and Synthesis of Ferrites
- Multiferroics and related materials
- Photochromic and Fluorescence Chemistry
- Synthesis and Properties of Aromatic Compounds
- Material Dynamics and Properties
- Photochemistry and Electron Transfer Studies
- Nonlinear Dynamics and Pattern Formation
- Nonlinear Optical Materials Research
- Image Retrieval and Classification Techniques
- Magnetic properties of thin films
- Electromagnetic wave absorption materials
- Plant Reproductive Biology
- Phase-change materials and chalcogenides
- Solid-state spectroscopy and crystallography
- Magneto-Optical Properties and Applications
- Chemical Thermodynamics and Molecular Structure
- Advanced Image and Video Retrieval Techniques
- Ferroelectric and Piezoelectric Materials
- Spectroscopy and Quantum Chemical Studies
- ZnO doping and properties
- Medical Image Segmentation Techniques
- Advanced Photocatalysis Techniques
Jawaharlal Nehru Technological University, Kakinada
2014-2023
Jawaharlal Nehru Technological University, Hyderabad
2004-2014
Acharya Nagarjuna University
1988-2001
Centre for Nano and Soft Matter Sciences
1996-2001
Abstract We report X-ray diffraction, density, ultrasonic velocity and refractive index studies in the N(p-n-pentyloxy benzylidene) p-n-alkylaniline compounds, viz. 50.5, 50.6 50.7. The nematic-smectic A (NA) transition is found to be weak first order while it second 50.5 salient features observed are cybotactic clusters nematic phase all molecular tilt which was inferred due end alkyl chains causing orienta-tional disorder (smaller orientational parameters 's' than expected) smectic phase,...
AbstractA new series of hydrogen bonded liquid crystal (HBLC) complexes, made up with substituted benzoic acids (BAs) and nonyloxy acid, viz., x-(p/m)BA:9OBAs are reported for x = F, Cl, Br –CH3 at para (p) or meta (m) positions BA moiety. Proton nuclear magnetic resonance (1H-NMR) spectrum confirms the HBLC complex. Infra red (IR) linear, double complementary type bonding (HB) between x-(p/m)BAs 9OBA. The (LC) phases characterised by polarisation optical microscopy (POM) differential...
The synthesis and characterization of five hydrogen-bonded ferroelectric liquid crystal complexes (HBFLCs) prepared from mesogenic p-n-alkoxy benzoic acids non-mesogenic propionic/butyric with different chiral centres are reported. Complementary intermolecular hydrogen bonding is confirmed through IR study. HBFLCs found to exhibit nematic (N*), smectic C* (SmC*) G* (monotropic) phases in their cooling profiles during polarizing thermal microscopy differential scanning calorimetry. Phase...
Abstract The density and refractive index variation with temperature in N(p-n-butoxybenzylidene)p-n-alkylanilines viz., 40.m compounds for m = 4 to 12 are presented. density, thermal expansion coefficient the results infer first order character IN, AB CB transitions a second NA AC transitions. Pretransitional effects discussed at IN odd-even effect is observed both phase of anisotropy as function temperature, nematic homologous series has shown an interesting phenomena. dependence yields...
Abstract The temperature dependence of density in terephthalylidene-p-n-decylaniline (TBAA10) is carried out to probe the phase transitions, associated volume jumps, order and estimate pressure transition temperatures pretransitional effects. compound exhibits smectic A, C, I, F G phases. isotropic-smectic A C-smectic I transitions are found he first calculated thermal expansion coefficient also supported results. A-smectic C for time I-smectic detectable by changes. from density-enthalpy...
Two novel series of unsymmetrically substituted 1,2,4-oxadiazole viz., R.Ox.C(*)C n compounds are synthesized and characterized. An optically active, (S)-(+)-methyl 3-hydroxy-2-methylpropionate is used to introduce a chiral center in the molecule. A biphenyl moiety prepared by Suzuki coupling reaction directly attached oxadiazole core at C-5 position. Investigations for phase behavior revealed that with benzyl group on one end exhibits an 1D orthogonal smectic-A while second dodecyl flexible...
Abstract The density and ultrasonic velocity of N(p-n-heptyloxybenzylidene) p-n-pentylaniline (70.5) are measured as a function temperature from the isotropic liquid to smectic B phase. compound is pentamorphic, exhibiting four phases, viz. G, B, C, A, nematic changes in density, derived parameters confirm N-I SB-SC transitions first-order, SA-N transition weak SC-SA second-order. An estimate pressure dependence temperatures presented. computed parameters: adiabatic compressibility β ad ,...
A novel series of linear hydrogen-bonded (HB) liquid crystalline (LC) complexes (HBLCs), namely Py16BA:noBAs, is reported. The was prepared by the complexation a non-mesogenic proton acceptor moiety, (4-pyridyl)-benzylidene-4′-n-hexadecyl aniline (Py16BA), with mesogenic donor, p-n-alkoxy benzoic acid (noBAs for n = 3, 4, 5, 6, 7, 8, 9, and 12) moieties. Formation HB confirmed through FTIR spectra. LC phases exhibited transition temperatures (Tc), heat (enthalpy) (ΔH) are determined...
Abstract The density, refractive index and ultrasonic velocity dependence on temperature for N(p-n-hexyloxy benzylidene) p-n-octyl aniline, 60.8, is presented. compound exhibits smectic B, A, nematic monotropic G phases between the solid isotropic liquid phases. nematic—isotropic A—smectic B phase transitions are found to be first order. interesting nematic—smectic A transformation confirmed a order from observed results. An estimate of pressure transition temperatures using volume enthalpy...
Abstract The nature of the nematic-smectic A (NA) phase transition is discussed in light available experimental data on N(p-n-pentyloxy benzylidene)p-n-alkyl anilines, 50.m series compounds. elucidate interesting aspects and it confirmed that homologues have a unique place nO.m NA transition, its dependence nematic thermal range, length alkoxy alkyl chains are discussed. evidence suggests presence TCP near homologues.
A novel series of linear hydrogen-bonded liquid crystals (HBLCs), viz., Py14BA:nFAs synthesized from nonmesogenic moieties, such as an N(p-n-pyridene carboxaldehyde), p-n-tetradecyl aniline, and the long-chain-bearing aliphatic acids (nFAs for n = 10, 12, 14, 16, 18), are reported. The chemical stability, purity sample, presence hydrogen bonding (HB) confirmed by polarized thermal microscopy 1H NMR IR spectroscopy. LC phase abundance is characterized optical (POM) differential scanning...
Vanadium metal oxide (V2O5) doped ZnO/SnS core-shell nanocomposites are fabricated by hydrothermal method at 2200C for 10 hours. All synthesized Nanocomposites were optically, structurally, morphologically and magnetically examined different techniques such as UV-DRS, XRD, TEM, electron paramagnetic resonance (EPR), XPS PL techniques. The photocatalytic activity (PCA) was studied methylene blue (MB) model pollutant dye under 300 W visible light illumination. XRD peaks confirmed the mixed...
Abstract Thermal microscopy (TM), differential scanning calorimetry (DSC) and dilatometric p(t) experiments were carried out to characterize the phases study nature of mesomorphic transitions in two higher homologues terephthalylidene-bis-p-n-alkylanilines, TBnAs, namely terephthalylidene-bis-p-n-tetradecylaniline, TB14A terephthalylidene-bis-p-hexadecylaniline, TB16A. Results infer first order isotropic-smectic C (I-Sc) smectic C-smectic I (Sc-SI) transitions, while I-smectic F (SI-SF)...