One-dimensional cyanide-bridged Fe(III)–Mn(II) magnetic complexes with different configurations derived from a new pentacyanoiron(III) building block

Influence of the Capping Ligands on the Self‐Assembly of Cyanido‐Bridged Mn(II)‐Fe(III) Aggregates: Synthesis, Crystal Structures, Electrochemical and Magnetic Properties

“…The deviation of χ M T product of 2 from the calculated χ M T value can be attributed to the presence of reasonable magnetic anisotropy due to zero field splitting in low spin octahedral Fe(III) ions (Table S7). Similar χ M T behaviour are observed in case of earlier reported cyanido bridged {Mn II Fe III } n chain structures [38,47–50] . On lowering the temperature, the χ M T product remains constant upto 59 K. Beyond 59 K, χ M T decreases rapidly to a minimum value of 0.57 cm 3 mol −1 K at 2 K. Such a magnetic behaviour for compound 2 can be attributed to intramolecular antiferromagnetic interactions between Mn(II) and Fe(III) ions [38,47–50] .…”

“…Isothermal field dependence of magnetization of compound 2 , measured at 2 K shows linear increase in magnetization with the increase in field strength (Figure 6, inset). Upon increasing magnetic field strength, magnetization increases linearly and reaches 3.19 N β until 5 T. The magnetization value approaches towards the theoretical saturation magnetization value of 4 N β for an antiferromagnetically coupled Mn(II)‐Fe(III) aggregate with ground spin state S=2 [38,47–50] …”

“…Similar χ M T behaviour are observed in case of earlier reported cyanido bridged {Mn II Fe III } n chain structures. [38,[47][48][49][50] On lowering the temperature, the χ M T product remains constant upto 59 K. Beyond 59 K, χ M T decreases rapidly to a minimum value of 0.57 cm 3 mol À 1 K at 2 K. Such a magnetic behaviour for compound 2 can be attributed to intramolecular antiferromagnetic interactions between Mn(II) and Fe(III) ions. [38,[47][48][49][50] The Curie-Weiss fit in the temperature range of 50 K to 300 K in 2 yielded Curie constant C of 4.94 cm 3 molK À 1 and Curie-Weiss constant, θ CW = À 0.90 K suggesting antiferromagnetic coupling between the Fe III and Mn II ions (Figure S22).…”

“…[38,[47][48][49][50] On lowering the temperature, the χ M T product remains constant upto 59 K. Beyond 59 K, χ M T decreases rapidly to a minimum value of 0.57 cm 3 mol À 1 K at 2 K. Such a magnetic behaviour for compound 2 can be attributed to intramolecular antiferromagnetic interactions between Mn(II) and Fe(III) ions. [38,[47][48][49][50] The Curie-Weiss fit in the temperature range of 50 K to 300 K in 2 yielded Curie constant C of 4.94 cm 3 molK À 1 and Curie-Weiss constant, θ CW = À 0.90 K suggesting antiferromagnetic coupling between the Fe III and Mn II ions (Figure S22). The experimental C value is in close agreement with the calculated value 4.75 cm 3 mol K À 1 for one isolated high spin Mn(II) (S = 5/2) and one isolated low spin Fe(III) (S = 1/2) considering g Mn = g Fe = 2.0.…”

“…Upon increasing magnetic field strength, magnetization increases linearly and reaches 3.19 Nβ until 5 T. The magnetization value approaches towards the theoretical saturation magnetization value of 4 Nβ for an antiferromagnetically coupled Mn(II)-Fe(III) aggregate with ground spin state S = 2. [38,[47][48][49][50]…”