Ahmed, M.Arachchige, K.S.A.Xie, Z.Price, J.R.Cruddas, J.Clegg, J.K.Powell, B.J.Kepert, C.J.Neville, S.M.2022-09-062022-09-062022Inorganic Chemistry, 2022; 61(30):11667-116740020-16691520-510Xhttps://hdl.handle.net/2440/136283A detailed study of the two-dimensional (2-D) Hofmann like framework [Fe(furpy)2Pd(CN)4]·nG (furpy: N-(pyridin-4-yl)furan-2- carboxamide, G = H2O,EtOH (A·H2O,Et), and H2O (A·H2O)) is presented, including the structural and spin-crossover (SCO) implications of subtle guest modification. This 2-D framework is characterized by undulating Hofmann layers and an array of interlayer spacing environments --this is a strategic approach that we achieve by the inclusion of a ligand with multiple host−host and host−guest interaction sites. Variable temperature magnetic susceptibility studies reveal an asymmetric multistep SCO for A·H2O,Et and an abrupt single-step SCO for A·H2O with an upshift in transition temperature of ∼75 K. Single-crystal analyses show a primitive orthorhombic symmetry for A·H2O,Et characterized by a unique FeII centers the multistep SCO character is attributed to local ligand orientation. Counterintuitively, A·H2O shows a triclinic symmetry with two inequivalent FeII centers that undergo a cooperative single-step high-spin (HS)-to-low-spin (LS) transition. We conduct detailed structure−function analyses to understand how the guest ethanol influences the delicate balance between framework communication and, therefore, the local structure and spin-state transition mechanism.en© 2022 American Chemical SocietyJournal article10.1021/acs.inorgchem.2c012532022-09-04617525