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Updated: Jun 13, 2026

Probing C84-embedded Si Substrate Using Scanning Probe Microscopy and Molecular Dynamics
Published on: September 28, 2016
SQSQh: (1)H-detected SQ-SQ experiment for determination of signed silicon-carbon coupling constants
Vratislav Blechta1, Jan Schraml
1Institute of Chemical Process Fundamentals of the ASCR, v. v. i., 165 02 Prague 6, Czech Republic. Blechta@icpf.cas.cz
Abstract:
A new variant of SQ-SQ pulse sequence (SQSQh) for relative sign determination and detection of small silicon-carbon couplings over more than one bond is presented. In the SQSQh sequence, proton detection replaces carbon detection used in the original SQ-SQ pulse sequence (SQSQc). The theoretical gain in sensitivity was experimentally tested on two samples (trimethylsiloxyethane, 1, and 1,2,4-tris(trimethylsiloxy)benzene, 2), the experimentally found gain provided by the SQSQh over the SQSQc method varied between 6 and 8. The method can be applied to linear spin systems, i.e. to systems where the silicon is coupled to the carbon in question and to any hydrogen not necessarily bonded to the carbon.
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