Related Experiment Video
Updated: Aug 6, 2026
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
When NMR predictions defy experimental crystal structures: the two-cluster anion [C2B10H11-C2B10H12]
1Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham DH1 3LE, UK. m.a.fox@durham.ac.uk.
Dalton Transactions (Cambridge, England : 2003)
|July 20, 2026
Summary
Crystal structures were re-examined using DFT NMR predictions. The study re-identifies a B-C bond between carborane clusters, correcting previous C-C bond assignments in related salts.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Computational Chemistry
Background:
- Carboranes are cage-like boron-containing compounds with diverse applications.
- Previous studies reported crystal structures of salts with two-cluster monoanions.
- These structures were interpreted as having a direct carbon-carbon bond between carborane units.
Purpose of the Study:
- To re-evaluate the bonding between carborane clusters in specific salts.
- To determine the accurate nature of the inter-cluster linkage.
- To validate computational predictions against crystallographic data.
Main Methods:
- Hybrid-density functional theory (DFT) calculations.
- GIAO-NMR (Gauge-Independent Atomic Orbital Nuclear Magnetic Resonance) spectroscopy predictions.
- Analysis of crystallographic data for three specific salts.
Main Results:
- The study re-interprets the bonding in the crystal structures.
- Accurate DFT GIAO-NMR predictions indicate an inter-cluster B-C bond, not a C-C bond.
- This finding corrects the previously proposed molecular geometry.
Conclusions:
- The bonding between the two carborane clusters in these salts is confirmed to be a B-C bond.
- Computational chemistry, specifically DFT GIAO-NMR, provides crucial insights for structural elucidation.
- This work refines the understanding of carborane cluster assembly and bonding.
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