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Updated: Aug 8, 2026
06:56
Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) Mass Spectrometry
Published on: June 10, 2018
Molecular adducts between a few phenolic donors and pi-acceptors in solid-state
A Ram Reddy1, N V Krishnamurthy, B Bhudevi
1Department of Chemistry, Nizam College, Osmania University, Hyderabad 500 001, AP, India. a_ramreddy@yahoo.com
Summary
Electron donor-acceptor complexes were formed via grinding or solution methods, yielding ionic, radical adducts. Stability depends on charge transfer, hydrogen bonding, and molecular structure.
Area of Science:
- Physical Chemistry
- Materials Science
- Spectroscopy
Background:
- Electron donor-acceptor (EDA) complexes are crucial in various chemical and physical processes.
- Understanding the formation, structure, and stability of EDA complexes is essential for designing new materials.
Purpose of the Study:
- To synthesize and characterize EDA molecular complexes using phenolic donors and quinonoid/tetracyanoethylene acceptors.
- To investigate the nature (ionic, radical) and stability of these complexes using spectroscopic methods.
Main Methods:
- Complex preparation via solid-state grinding and solution methods.
- Characterization using Electron Spin Resonance (ESR) spectroscopy, electronic absorption spectroscopy, Infrared (IR) spectroscopy, and Proton Nuclear Magnetic Resonance (NMR) spectroscopy.
Main Results:
- Identical 1:1 stoichiometric, dark-colored complexes were formed by both methods.
- Spectral studies confirmed the ionic nature and free radical character (g values 2.000–2.022) of the adducts.
- Electronic absorption revealed charge transfer bands (>or=550 nm) and anion radical transitions (~410 nm); stability is influenced by ionization potential, electron affinity, and molecular structure.
Conclusions:
- The study successfully prepared and characterized novel EDA complexes.
- Complex stability is governed by a combination of charge transfer interactions and hydrogen bonding, alongside structural factors.
- Spectroscopic techniques provide valuable insights into the electronic and structural properties of these molecular adducts.
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