NuMega Resonance Labs

Silicon NMR

NMR Testing Services, Mass Spec, Elemental Analysis and Optical Rotation

Silicon can be found in many materials ranging from hardware such as glass and electronic components to cosmetics and high-performance fluids. It is also commonly used as protecting groups in organic synthesis. Structural characterization of silicon based materials can be achieved through Si-29 NMR which is often used to characterize siloxane polymers.

Similar to H-1 and C-13, Tetramethylsilane (TMS) is commonly used as an internal standard for Si-29 NMR as a zero point. Common chemical shifts are listed above for variations of the silicon structure. While Si-29 NMR has medium sensitivity in comparison to other nuclei, the relaxation time required is usually longer. Additionally, it has a negative gyromagnetic ratio thus requiring inverse gated decoupling pulse sequences. Unfortunately, since silicon is common in many different materials, components of the NMR probe itself will give off a broad signal in the Si-29 NMR spectra. While silicon based materials come in many forms, we only perform NMR on samples which can be dissolved in a solvent.