A [3Fe-3S](3+) cluster with exclusively μ-sulfide donors

Area of Science:

• Inorganic chemistry
• Bioinorganic chemistry
• Magnetochemistry

Background:

• Iron-sulfur clusters are crucial in biological electron transfer.
• Understanding the structure-property relationships of these clusters is vital.
• Novel cluster geometries and electronic structures offer new insights.

Purpose of the Study:

• To report the synthesis and characterization of a novel [3Fe-3(μ-S)](3+) cluster.
• To investigate the geometric and electronic properties of the ferric centers.
• To determine the ground state and magnetic properties of the cluster.

Main Methods:

• Variable temperature magnetometry
• Mössbauer spectroscopy
• Single-crystal X-ray diffraction (implied for geometry determination)

Main Results:

• A [3Fe-3(μ-S)](3+) cluster with distorted trigonal pyramidal ferric centers was synthesized.
• An S = 1/2 ground state for the cluster was determined.
• Unusually anisotropic hyperfine coupling constants were observed.

Conclusions:

• The study presents a new type of iron-sulfur cluster.
• The observed magnetic properties are attributed to the unique geometry and electronic structure.
• This work expands the known diversity of iron-sulfur cluster structures and properties.