Ebenezer
@americancollege.edu.in
Assistant Professor
The American college
RESEARCH INTERESTS
Chemistry
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
M. Shyamala Devi, P. Tharmaraj, C. D. Sheela, and R. Ebenezer
Springer Science and Business Media LLC
Three novel triazine based organic chromophores with D-π-A (Donor-π system- Acceptor) push-pull type have been synthesized from 2, 4-diamino-6-phenyl-1,3,5-triazine as a starting material. Structures of all the three compounds have been confirmed by UV-Visible absorption, FT-IR, NMR and Mass spectral techniques. Their photo physical and thermal properties have been investigated. Among the three compounds, 6-phenyl-2,4-((4-amino-1,5-dimethyl-2-phenyl pyrazol-3-ylidene)(4-nitro benzylidene))-diamino-1, 3, 5-triazine (NDP) showed positive solvatochromism compared to the other two compounds. The absorption in the UV region of these three compounds were found to be less dependent on solvent polarities, whereas the red shifted fluorescence was strongly dependent on solvent polarities. The TGA data indicates that all the three compounds are stable up to 160 °C. Measurement of non linear optical properties showed that there is an increased second harmonic generation (SHG) efficiency with respect to urea indicating the existence of high molecular nonlinearity in NDP.
S. Sumathi, P. Tharmaraj, C.D. Sheela, and R. Ebenezer
Informa UK Limited
A series of metal(II) complexes ML [where M = Cu(II), Co(II), Ni(II), Zn(II)] have been prepared from [4-((1H-indol-3-yl)methylene)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione] (IMHH) and 2,4-diamino-6-phenyl-1,3,5-triazine. The structures of the complexes have been investigated by using elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, mass, NMR, and ESR spectral studies. Conductivity measurements reveal that all the complexes are electrolytes. Spectral and other data show either octahedral or square-pyramidal geometry for all the complexes. Redox behavior of the copper(II) complex has been studied through cyclic voltammetry. Antimicrobial activities of the compounds were studied against several microorganisms with all the complexes having higher activity than free ligand. All the compounds may serve as potential photoactive materials as indicated from their fluorescence properties. The second harmonic conversion efficiency of the ligand has been found to be higher than that of urea and KDP.
S. Sumathi, P. Tharmaraj, C.D. Sheela, and R. Ebenezer
Informa UK Limited
A series of metal(II) complexes ML and ML2 [where M = Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II), and VO(II); L = 2-hydroxyphenyl-3-(1H-indol-3-yl)-prop-2-en-1-one (HPIP)] have been prepared and characterized by elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, NMR, Mass, and ESR spectral studies. Conductivity measurements reveal that the complexes are non-electrolytes, except VO(II) complex. Spectroscopy and other data show square pyramidal geometry for oxovanadium and octahedral geometry for the other complexes. Redox behavior of the copper(II) and vanadyl complexes has been studied with cyclic voltammetry. Antimicrobial activities against several microorganisms indicate that a few complexes exhibit considerable activity. The nuclease activity shows that the complexes cleave DNA. All synthesized compounds can serve as potential photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation efficiency of the ligand is higher than that of urea and KDP.
S. Sumathi, P. Tharmaraj, C.D. Sheela, R. Ebenezer, and P. Saravana Bhava
Informa UK Limited
A series of metal(II) complexes ML (where M = Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II), and VO(II)) have been prepared from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one and sulfanilamide. The structures of the complexes have been investigated by elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, NMR, mass, and ESR spectral studies. Conductivity measurements reveal that the complexes are non-electrolytes, except the oxovanadium complex. Spectral and other data show square pyramidal geometry for oxovanadium and octahedral for the other complexes. The redox behaviors of the copper and vanadyl complexes have been studied through cyclic voltammetry. Antimicrobial activities of the compounds against several microorganisms indicate that some complexes have higher activity than free ligand. The compounds may serve as photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation efficiency of the ligand was found to be higher than that of urea and KDP.