Samarium Polystibides Derived from Highly Activated Nanoscale Antimony

Area of Science:

• Inorganic Chemistry
• Materials Science
• Coordination Chemistry

Background:

• Zintl ions are crucial in molecular compounds for both research and practical applications.
• Developing efficient synthetic routes to polystibide compounds remains an active area of research.

Purpose of the Study:

• To present novel reactive antimony sources for synthesizing molecular polystibide compounds.
• To achieve direct access to the largest f-element polystibide, [(Cp*2Sm)4Sb8].
• To elucidate the formation mechanism of polystibide compounds.

Main Methods:

• Utilizing antimony amalgam (Sb/Hg) and ultrasmall antimony (Sb0) nanoparticles as antimony precursors.
• Reacting these precursors with [Cp*2Sm] (Cp* = pentamethylcyclopentadienyl).
• Isolation and structural characterization of intermediate samarium-antimony-mercury (Sm/Sb/Hg) species.

Main Results:

• Successful synthesis of the largest f-element polystibide, [(Cp*2Sm)4Sb8], using both Sb/Hg and Sb0 nanoparticles.
• Isolation and characterization of novel Sm/Sb/Hg intermediates: [{(Cp*2Sm)2Sb}2(μ-Hg)] and [{(Cp*2Sm)3(μ4,η1:2:2:2-Sb4)}2Hg].
• Direct formation of [(Cp*2Sm)4Sb8] from Sb0 nanoparticles and [Cp*2Sm].

Conclusions:

• Antimony amalgam and nanoparticles offer versatile pathways to molecular polystibides.
• The characterized Sm/Sb/Hg intermediates provide crucial mechanistic insights into polystibide formation.
• This study expands the scope of accessible f-element polystibide chemistry.