Studies on vibrational, dielectric, mechanical and thermal properties of organic nonlinear optical co-crystal: 2,6-diaminopyridinium4-nitrophenolate4- nitrophenol

Research output: Contribution to journalArticleScientificpeer-review


Research units

  • Periyar University
  • National Institute of Technology Tiruchirappalli


This article presents the vibrational, dielectric, mechanical and thermal properties of 2,6-diaminopyridine4-nitrophenolate4-nitrophenol co-crystals (DAP:NP) grown by slow evaporation solution growth technique. It crystallizes in orthorhombic noncentrosymmetric space group Pna2 1 with cell dimension a=10.86 Å, b=12.00 Å and c=13.53 Å; α=β=γ=90°with V=1764 Å 3. Functional groups present in the molecule have been identified from FTIR study. Dielectric constant (ε r), dielectric loss (tanδ) and ac conductivity (σ ac) behaviors of the crystals have been studied at different temperatures. Presence of piezoelectric resonance peaks at lower frequency in dielectric measurements may increase the electro-optic coefficient of the crystals. Mechanical strength and its parameters of the grown crystals have been determined by Vickers microhardness test. TG/DTA analysis shows the melting point of the material is 150°C and it undergoes two stages of decomposition.


Original languageEnglish
Pages (from-to)1119-1123
Number of pages5
JournalPhysica B: Condensed Matter
Issue number7
Publication statusPublished - 1 Apr 2012
MoE publication typeA1 Journal article-refereed

    Research areas

  • Crystal growth, Dielectrics, Microhardness, Thermal study, X-ray diffraction

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