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Updated: May 7, 2026

Iridium(III) Luminescent Probe for Detection of the Malarial Protein Biomarker Histidine Rich Protein-II
Published on: July 7, 2015
Structure and spectral properties of L-histidinium dipicrate dihydrate
M Sethuram1, M Dhandapani, M Sethu Raman
1Post Graduate and Research Department of Chemistry, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020, Tamil Nadu, India.
Abstract:
Non-linear optical active L-histidinium dipicrate dihydrate (LHDD) single crystals were grown by slow evaporation method. The Fourier transform FT-IR, FT-Raman, (1)H and (13)C NMR spectra of the crystal have been recorded and analysed. The spectral analyses confirm the formation of the compound and the stoichiometry. The geometry and spectral characteristics were examined using the density functional theory (DFT) method, B3LYP with 6-31G(d,p) basis set. The first-order hyperpolarisability, energies of frontier molecular orbitals and the Mulliken population analysis were also calculated. The HOMO-LUMO energy gap value 2.73 eV indicates the charge transfer from picrate to histidinium through the hydrogen bond. The second-order NLO properties of the molecule are studied by Kurtz-Perry powder technique. SHG efficiency of the compound is nearly 2.5 times greater than KDP. Theoretical calculations indicate hyperpolarisability of LHDD is 39 times greater than urea. The results show that the title molecule can be used for opto-electronic applications.
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