Figure 22.

(left) AFM pattern recorded in tapping mode at room temperature on hexagonal single crystals of [Fe₃(hyetrz)₆(H₂O)₆](CF₃SO₃)₆. A domain size of ~10–20 nm was identified [239]. The insert shows the crystal structure of the trinuclear unit as well as the noncoordinated anion [98]. (right) χ_MT versus T showing a gradual spin conversion from [HS–LS–HS] trimers below ~250 K to [HS–HS–HS] trimers above ~350 K. The color of the crystals is shown as well as ΔT₈₀, which represents the temperature interval for which 80% of ions have switched [98].