Host-Guest Hydrogen Bonding Varies the Charge-State Behavior of Magnetic Sponges.

The electron-donor(D) and -acceptor(A)-assembled D ₂ A-layer framework [{Ru ₂ (m-FPhCO ₂ ) ₄ } ₂ TCNQ(OMe) ₂ ]⋅nDCE (1-nDCE; m-FPhCO ₂ ^- =m-fluorobenzoate; TCNQ(OMe) ₂ =2,5-dimethoxyl-7,7,8,8-tetracyanoquinodimethane; DCE=1,2-dichloroethane) undergoes drastic charge-ordered state variations via three distinct states that are a two-electron-transferred state (2e-I), a charge-disproportionated state (1.5e-I), and a one-electron-transferred state (1e-I), depending on the degree of solvation by nDCE. The pristine form 1-4DCE has a paramagnetic 2e-I state, which eventually produces the solvent-free form 1 in 1.5e-I via an intermediate state 1-nDCE (n≤1) in 1e-I. Resolvation of 1 stabilizes 1-DCE, allowing it to switch between 1.5e-I and 1e-I, and to become ferrimagnetic with a T _c of 30 K (1.5e-I) and 88 K (1e-I). The stabilization of the 1e-I state of 1-DCE is due to the presence of host-guest hydrogen bonding that enables to suppress the electron-donation ability of D even in an identical framework with 1.
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