Spin Crossover Phenomenon in Coordination Compounds

Surface and Size Effects in Spin-Crossover Nanocrystals

“…They show a general tendency that the hysteresis cannot take place for particularly small nanoparticles. In excellent agreement with experiment reported in [24], we have found that the hysteresis width vanishes at a critical particle size. This is a consequence of the different intrinsic cooperative nature of the physical phenomenon on surface and inside the solid.…”

Pressure Tunable Electronic Bistability in Fe(II) Hofmann-like Two-Dimensional Coordination Polymer [Fe(Fpz)2Pt(CN)4]: A Comprehensive Experimental and Theoretical Study

“…Molecular materials based on transition-metal coordination compounds are at the forefront of research in material science since they bear the potential to technically solve modern society concerns, such as air and water pollution, energy storage and transport, and data storage and display as well. − In this context, the study over decades of the molecular electronic bistability exhibited by Fe­(II) pseudo-octahedral coordination compounds, known as the spin crossover phenomenon (SCO) or spin transition (ST), − has brought a variety of molecular sensors capable of sensing, capturing, and storaging gases − or organic volatile compounds and water pollutants. − In addition, prototypes of pressure or temperature sensors, actuators, and switches have been developed for civil applications, ,− and even a sensor that transduces an electrical voltage variation into an optical output has been reported …”

Electrical Voltage Control of the Pressure-Induced Spin Transition at Room Temperature in the Microporous 3D Polymer [Fe(pz)Pt(CN)4]

“…These characteristics have created prospects for exploitation in the storage of fuels (H 2 and CH 4 ), capture of pollutants (CO 2 , NO 2 , SO 2 ), and use as catalyst and as drug delivers, etc. Advanced PCP exhibit, apart from the porous properties, other physical properties, for example, spin state switching, magnetic coupling, proton or electron conduction, fluorescence, mechanical motion, etc. − The spin state switching (ST) or spin crossover phenomena (SCO) − have mainly been reported on PCP based on iron­(II)–metallocyanate inorganic building blocks. − The molecular Fe­(II) switches produce outputs such as changes in absorbance, refractive index, crystal and molecular structure, and magnetic and dielectric responses. It then becomes possible to associate a piece of information with each of the low spin (LS) and high spin (HS) states.…”

“…Pressure has been shown to be a useful tool to enhance the pore size and sorption capabilities of selected PCP. , However, in other cases, application of pressure promotes the release and restricts the absorption and diffusion of guest molecules through the porous crystalline framework . Recently, the study of the temperature induced spin transition (TIST) − at various hydrostatic pressures as well as the studies of pressure induced spin transition (PIST) − at constant temperature for {Fe­(pz)­[Pt­(CN) 4 ]} have been reported (Figures S1 and S2). These studies demonstrated that TIST is inhibited at a critical pressure of ca.…”