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Synergetic Spin-Crossover and Luminescent Properties in a Multifunctional 2D Iron(II) Coordination Polymer
Jia Wang1, Ming Kong1, Xiao-Jiao Song1,2
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, P. R. China.
Abstract:
We designed and synthesized a strong fluorescent tetradentate pyridine ligand, 3,6,11,12-tetra(pyridin-4-yl)dibenzo[a,c]phenazine (TPDP), by covalently grafting pyridyl to fluorescent dye dbpz, which can react with the Fe(NCX)2 (X = S and Se) unit, obtaining two new 2D [4 × 4] square-grid compounds, namely, {FeII(TPDP)2(SCN)2·CHCl3·4CH3OH} (1) and {[FeII(TPDP)2(SeCN)2]·CH2Cl2·4CH3OH} (2). Both of them show expected one-step spin-crossover (SCO) properties, and complex 2 exhibits a combination of the SCO phenomenon and fluorescence in a synergetic way. The energy transfer mechanism of 2 is verified by the theoretical calculations and experimental results. This study provides an effective strategy to synthesize large conjugated fluorescent ligands using dyes to further form SCO-luminescent bifunctional materials.
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