Enforcing Multifunctionality: A Pressure-Induced Spin-Crossover Photomagnet

Photomagnetic compounds are usually
achieved by assembling preorganized
individual molecules into rationally designed molecular architectures
via the bottom-up approach. Here we show that a magnetic response
to light can also be enforced in a nonphotomagnetic compound by applying
mechanical stress. The nonphotomagnetic cyano-bridged FeII–NbIV coordination polymer {[FeII(pyrazole)4]2[NbIV(CN)8]·4H2O}n (FeNb) has been
subjected to high-pressure structural, magnetic and photomagnetic
studies at low temperature, which revealed a wide spectrum of pressure-related
functionalities including the light-induced magnetization. The multifunctionality
of FeNb is compared with a simple structural and magnetic
pressure response of its analog {[MnII(pyrazole)4]2[NbIV(CN)8]·4H2O}n (MnNb). The FeNb coordination polymer is the first pressure-induced spin-crossover
photomagnet.