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Published on: December 27, 2018
Azo-azulene derivatives as second-order nonlinear optical chromophores
1Laboratoire de Chimie de Coordination (CNRS), Toulouse, France. pascal@lcc-toulouse.fr
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 29, 2000
Summary
Researchers explored nonlinear optical (NLO) properties of azo-azulenes. (4-nitrophenylazo)-azulene showed significant potential for second-harmonic generation, 420 times greater than urea.
Area of Science:
- Materials Science
- Optics
- Crystallography
Background:
- Nonlinear optical (NLO) materials are crucial for advanced photonic applications.
- Azo-azulene derivatives are a class of organic compounds with potential NLO properties.
- Understanding structure-property relationships is key to designing efficient NLO materials.
Purpose of the Study:
- To investigate the molecular and solid-state NLO properties of novel (phenylazo)-azulenes.
- To evaluate the potential of (4-nitrophenylazo)-azulene as an efficient NLO material.
- To correlate NLO response with crystal structure and electronic properties.
Main Methods:
- Electric Field-Induced Second-Harmonic (EFISH) technique was used to measure quadratic hyperpolarizability (β).
- X-ray crystallography was employed to determine the crystal structure of (4-nitrophenylazo)-azulene.
- Semiempirical calculations (INDO/SOS formalism) were performed to understand electronic contributions.
Main Results:
- (4-nitrophenylazo)-azulene (2b) demonstrated a high quadratic hyperpolarizability (β) of 80 x 10⁻³⁰ cm⁵esu.
- This compound crystallizes in a noncentrosymmetric monoclinic space group Pc.
- Second-harmonic generation efficiency was found to be 420 times that of urea.
Conclusions:
- (4-nitrophenylazo)-azulene exhibits significant potential for NLO applications due to its strong nonlinear response.
- The observed NLO properties are linked to its molecular structure and crystal packing.
- This study provides valuable insights for the development of advanced organic NLO materials.
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