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Updated: Jun 18, 2025
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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
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Why Are Some Pnictogen(III) Pincer Complexes Planar and Others Pyramidal?
Tyler J Hannah1, Tamina Z Kirsch1, Saurabh S Chitnis1
1Chemistry Department, Dalhousie University, 6243 Alumni Crescent, B3H4R2, Halifax, Nova Scotia, Canada.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 30, 2024
Summary
A new model explains pnictogen pincer complex geometries by balancing opposing sigma and pi bonding effects. This framework predicts and aids in designing complexes with specific conformations and reactivities.
Area of Science:
- Organometallic Chemistry
- Computational Chemistry
- Materials Science
Background:
- Pnictogen pincer complexes exhibit diverse geometries crucial for their reactivity.
- Existing models lack a unified explanation for observed conformational variations.
Purpose of the Study:
- To develop a unified computational model explaining the conformational diversity of pnictogen pincer complexes.
- To predict and guide the rational design of these complexes.
Main Methods:
- Computational analysis of over 1300 structures across 64 complexes.
- Examination of bond stability (bond lengths, Wiberg bond indices) and charge delocalization (NPA, Hirshfeld charges).
Main Results:
- A model is proposed based on competing pnictogen-based σ-bonding (favoring pyramidalization) and ligand-based π-bonding (favoring planarity).
- Structural variations are reconciled by the balance between these opposing forces.
Conclusions:
- The proposed σ/π-bonding model successfully explains observed geometries and predicts future outcomes.
- This framework can aid in the rational design of pnictogen pincer complexes with tailored properties.
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