Switchable on–off spin-crossover properties of iron(ii) compounds by trimming intermolecular hydrogen bonds

Reversible single crystal-to-single crystal transformations from [FeL2(NCS)2]·3MeOH (1·3MeOH, L = 2 (anthracen-10-yl) 1H imidazo[4,5 f][1,10]phenanthroline) to 1 and 1·2H2O were reported, which were accompanied with on-off switching in the spin-crossover properties.