Browsing by Author "Swamynathan, K."

Now showing 1 - 4 of 4

Columnar self-assembly of novel benzylidenehydrazones and their difluoroboron complexes: Structure-property correlations
(2019) Vinayakumara, D.R.; Swamynathan, K.; Kumar, S.; Adhikari, A.V.
Organoboron complexes are considered to be an important class of optically dynamic materials and because of their imperative properties, they have been unceasingly studied in a wide range of scientific areas. In this context, a new family of D-A-D? architectured boron difluoride complexes FB1-4 derived from arylhydrazones HZ1-4 has been synthesized and characterized. The work also deliberates detailed studies on their thermal, self-assembling and optoelectronic properties with respect to structural modifications. The systematic studies reveal that the new arylhydrazone ligands and their BF2 complexes exhibit a prospective columnar mesomorphism with different 2D lattice geometries at room temperature, owing to their critical structural features. Interestingly, an unusual morphological cross-over from a columnar hexagonal to rectangular mesophase has been confirmed in one of the investigated pseudo-discoidal boron complexes, FB4. The optoelectronic studies showcased their ICT dominating dye properties. Finally, the experimental results have been consciously correlated with quantum chemical simulations. 2019 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Columnar self-assembly of novel benzylidenehydrazones and their difluoroboron complexes: Structure-property correlations
(Royal Society of Chemistry, 2019) Vinayakumara, D.R.; Swamynathan, K.; Kumar, S.; Vasudeva Adhikari, A.V.
Organoboron complexes are considered to be an important class of optically dynamic materials and because of their imperative properties, they have been unceasingly studied in a wide range of scientific areas. In this context, a new family of D-A-D? architectured boron difluoride complexes FB1-4 derived from arylhydrazones HZ1-4 has been synthesized and characterized. The work also deliberates detailed studies on their thermal, self-assembling and optoelectronic properties with respect to structural modifications. The systematic studies reveal that the new arylhydrazone ligands and their BF2 complexes exhibit a prospective columnar mesomorphism with different 2D lattice geometries at room temperature, owing to their critical structural features. Interestingly, an unusual morphological cross-over from a columnar hexagonal to rectangular mesophase has been confirmed in one of the investigated pseudo-discoidal boron complexes, FB4. The optoelectronic studies showcased their ICT dominating dye properties. Finally, the experimental results have been consciously correlated with quantum chemical simulations. © 2019 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Optoelectronic exploration of novel non-symmetrical star-shaped discotic liquid crystals based on cyanopyridine
(2018) Vinayakumara, D.R.; Swamynathan, K.; Kumar, S.; Adhikari, A.V.
A novel family of non-symmetrical star-shaped cyanopyridine based discotic liquid crystals (CPBz6, CPBz8 and CPBz12) was designed and synthesized, as potential luminescent materials for optoelectronic applications. The length of one of the arms in the design was systematically varied to determine the structure-property relationships. Evidently, all of the compounds exhibited a highly prospective ordered columnar mesomorphism stabilized at ambient temperature with advantageous very low isotropization temperatures. Furthermore, their photophysical characteristics were investigated in depth, both in solution and in the liquid crystal (LC) state. The discotics were found to be intense blue emitters with reasonably good quantum efficiency. Their dynamic intramolecular charge-transfer (ICT) behaviour was confirmed by steady-state absorption and fluorescence spectral analysis in varied solvent polarity. Furthermore, their electrochemical properties were studied from the combination of an experimental method and the theoretical simulations, which elucidated the low laying frontier molecular orbitals (FMOs) with a narrow energy band gap of ?2.0 eV. The resulted visually perceivable emission with favourable energy levels showcases their possible application in electronic display devices. 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Optoelectronic exploration of novel non-symmetrical star-shaped discotic liquid crystals based on cyanopyridine
(Royal Society of Chemistry, 2018) Vinayakumara, D.R.; Swamynathan, K.; Kumar, S.; Vasudeva Adhikari, A.
A novel family of non-symmetrical star-shaped cyanopyridine based discotic liquid crystals (CPBz6, CPBz8 and CPBz12) was designed and synthesized, as potential luminescent materials for optoelectronic applications. The length of one of the arms in the design was systematically varied to determine the structure-property relationships. Evidently, all of the compounds exhibited a highly prospective ordered columnar mesomorphism stabilized at ambient temperature with advantageous very low isotropization temperatures. Furthermore, their photophysical characteristics were investigated in depth, both in solution and in the liquid crystal (LC) state. The discotics were found to be intense blue emitters with reasonably good quantum efficiency. Their dynamic intramolecular charge-transfer (ICT) behaviour was confirmed by steady-state absorption and fluorescence spectral analysis in varied solvent polarity. Furthermore, their electrochemical properties were studied from the combination of an experimental method and the theoretical simulations, which elucidated the low laying frontier molecular orbitals (FMOs) with a narrow energy band gap of ?2.0 eV. The resulted visually perceivable emission with favourable energy levels showcases their possible application in electronic display devices. © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.