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Spin crossover in 2D iron(ii) phthalazine cyanometallic complexes.
Volodymyr M Hiiuk1, Sergiu Shova2, Aurelian Rotaru3
1Department of Chemistry, Taras Shevchenko National University of Kyiv, 64 Volodymyrska St., 01601 Kyiv, Ukraine. illia.guralskyi@univ.kiev.ua and UkrOrgSyntez Ltd., 67 Chervonotkatska St., 02094 Kyiv, Ukraine and Faculty of Natural Sciences, National University of Kyiv-Mohyla Academy, 2 Skovorody St., 04070 Kyiv, Ukraine.
Two new spin-crossover (SCO) materials based on iron(II) complexes with phthalazine ligands were synthesized. These novel SCO analogues exhibit switchable behavior and narrow thermal hysteresis, paving the way for new switchable complex designs.
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Spin-crossover (SCO) materials are known for their potential in molecular switches and memory devices.
- Hofmann clathrates are a class of coordination compounds with potential for SCO behavior.
Purpose of the Study:
- To synthesize and characterize new 2D spin-crossover (SCO) analogues of Hofmann clathrates.
- To investigate the structural and switchable properties of novel iron(II) complexes incorporating phthalazine ligands.
Main Methods:
- Single-crystal X-ray diffraction for structural analysis.
- Temperature-dependent magnetic susceptibility measurements to study SCO behavior.
- Optical measurements, differential scanning calorimetry, and vibrational spectroscopy (IR and Raman) for characterization.
Main Results:
- Two new 2D SCO analogues, [Fe(phth)2MII(CN)4] (MII = Pd, Pt), were successfully synthesized.
- Structural analysis confirmed octahedral coordination of FeII centers stabilized by supramolecular interactions.
- Both Pt and Pd derivatives exhibited cooperative spin crossover with narrow thermal hysteresis loops.
Conclusions:
- Phthalazine ligands enable the creation of new SCO systems with desirable transition characteristics.
- These findings open new avenues for designing switchable complexes using fused bicyclic azine ligands.
- The synthesized complexes demonstrate potential for applications in molecular switching and data storage.
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