Effects of the Inverse Trans-Influence in a Berkelium(III) Phosphine Oxide Complex

Area of Science:

• Inorganic Chemistry
• Actinide Chemistry
• Coordination Chemistry

Background:

• The inverse trans-influence (ITI) is a phenomenon observed in coordination complexes.
• Understanding ITI in late actinides is crucial for predicting their chemical behavior.

Purpose of the Study:

• To prepare and characterize a berkelium(III) phosphine oxide complex.
• To quantify the ITI effects in a late actinide complex.
• To compare Bk-ligand bond properties with lanthanide analogues.

Main Methods:

• Synthesis of the meridional berkelium(III) complex, BkBr3(OPCy3)3.
• Detailed bond metric analysis of Bk-ligand bonds.
• Calculation of ITI values for the trans Bk3+-O bond.

Main Results:

• The shortest reported Bk3+-O bond distance was observed.
• The ITI value for the trans Bk3+-O bond was 98.5(2)%, comparable to americium analogues.
• A small 5f orbital contribution to bonding was indicated.

Conclusions:

• The ITI in the studied berkelium complex is significant and comparable to related actinides.
• The 5f orbital contribution to bonding in this complex is minimal.
• The ITI in berkelium complexes may differ from lanthanide analogues.