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Published on: May 15, 2017
Stepwise neutral-ionic phase transitions in a covalently bonded donor/acceptor chain compound
Hitoshi Miyasaka1, Natsuko Motokawa, Tamiko Chiyo
1Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Sendai 980-8578, Japan. miyasaka@se.kanazawa-u.ac.jp
Journal of the American Chemical Society
|March 18, 2011
Summary
This study reveals stepwise neutral-ionic transitions in a metal-complex donor/acceptor chain, driven by Coulomb interactions. This stepwise behavior offers new possibilities for controlling charge and spin functionalities.
Area of Science:
- Materials Science
- Solid State Physics
- Chemistry
Background:
- Neutral (N)-ionic (I) transitions in organic donor (D)/acceptor (A) complexes offer diverse functionalities.
- Controlling these transitions requires tuning ionization potential and electron affinity.
- The role of Coulomb interactions in stepwise N-I transitions remains unclear.
Purpose of the Study:
- To provide definitive evidence for stepwise N-I transitions.
- To investigate the influence of anisotropic interchain Coulomb interactions.
- To explore the resulting variations in spin-ground states and magnetic ordering.
Main Methods:
- Synthesis and characterization of a metal-complex-based covalently bonded DA chain compound: [Ru(2)(2,3,5,6-F(4)PhCO(2))(4)(DMDCNQI)]·2(p-xylene).
- Temperature-dependent measurements to observe phase transitions.
- Analysis of charge, spin, and lattice properties.
Main Results:
- Observed stepwise N-I transitions in the intermediate temperature range (210 K–270 K).
- Identified self-organized N and I chains in this phase.
- Demonstrated variations in spin-ground states and ferrimagnetic ordering in the ionic phase.
Conclusions:
- Anisotropic interchain Coulomb interactions drive stepwise N-I transitions.
- The stepwise transition exhibits a highly sensitive magnetic response.
- This phenomenon opens avenues for new dynamical functionalities in charge, spin, and lattice systems.
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