Covalent post-synthetic modification of switchable iron-based coordination polymers by volatile organic compounds: a versatile strategy for selective sensor development

Abstract

A covalent post-synthetic modification is applied in one of the most relevant polymers to obtain unprecedented switchable spin crossover (SCO) materials.

Biased Spin-State Energetics of Fe(II) Molecular Complexes within Density-Functional Theory and the Linear-Response HubbardUCorrection

“…[1][2][3][4][5][6][7][8] Achieving such a description with chemical accuracy appears today as a significant challenge for ab initio methods with strong implications in future assistance and guidance of experimental efforts devoted to the (i) development and optimization of catalytic reactivity and the (ii) design of novel spin crossover (SCO) complexes. The vast majority of SCO materials, which are of great interest for applications such as molecular spintronics, molecular electronics, sensors and actuators, [9][10][11][12] are octahedrallycoordinated Fe(II)-based molecular complexes. For these complexes, the thermodynamics of the spin transition (i.e.…”

Complete and Versatile Post‐Synthetic Modification on Iron‐Triazole Spin Crossover Complexes: A Relevant Material Elaboration Method

“…This hypothesis is supported by different results described in the literature: 1) it is well known that molecules can be inserted between 1D polymer chains; [104][105][106] 2) different examples of PSM on polymers [107,108] and on montmorillonite sheets [109] have been also reported 3) full PSM modification in Fe-triazole chains has been already reported for solid vapor reactions. [50] The study of the spin crossover properties is also in line with a complete PSM reaction. Through the Mössbauer measurements for the different samples, we observed that at 80 K the majority of the iron centers are in the LS state, in agreement with the variabletemperature magnetic measurements.…”

“…To the best of our knowledge, concerning this family of compounds, only formations of imine by PSM methodology were described in the literature. [46][47][48]50] When it was possible, we also prepared corresponding materials using the direct synthesis (DS) method in order to ease the characterization of the desired compound.…”

“…To the best of our knowledge, few examples using this methodology for SCO materials are described in the literature. They consist of post-functionalization of 3D Hofmann clathrate MOF, [41,42] a dinuclear iron(III) complex, [43] a Fe II [M IV (CN) 8 ] 4 À (M=Mo, Nb) cyanido-Bridged Framework, [44] 1D polymeric iron-triazole complexes [45][46][47][48][49][50] and of iron poly(pyrazolyl)borate complexes. [51,52] In 2001, Saf et al [49] published the synthesis of a spin crossover material, for which the last step of the synthesis corresponds to the polymerization of the methacrylate substituent present on the triazole ligand.…”

“…The work done by Wang et al [47,48] consisted in introducing luminescent properties on an iron-triazole SCO complex by PSM reactions, with different fluorophores like anthracene or pyrene in low yields (up to 15 %). Very recently, Costa et al [50] published a complete PSM method resulting from a reaction between the [Fe(NH 2 trz) 3 ]X 2 (X=OTs) complex and vapors of aldehyde or ketones. Following our previous results [46] for which a complete PSM reaction was achieved on an iron-triazole SCO complex [Fe(NH 2 trz) 3 ](NO 3 ) 2 (with NH 2 trz = 4-amino-1,2,4-triazole), we are interested to study the PSM methodology on this family of compounds with a variety of substrates, in order to confirm the efficiency and show the versatility of such approach.…”