In the realm of Nuclear Magnetic Resonance (NMR) spectroscopy, the choice of an internal standard is critical for calibrating chemical shifts and ensuring accurate data interpretation. Two commonly used silicon-containing compounds for this purpose are Hexamethyldisiloxane (HMDSO) and Tetramethylsilane (TMS). While both serve as excellent reference points due to their high symmetry and single NMR signal, HMDSO offers distinct advantages in handling and certain niche applications. As a supplier of high-quality organosilicon compounds, we aim to clarify these differences to help you make an informed choice.

Tetramethylsilane (TMS): The Traditional Standard
TMS (Si(CH3)4) has long been the default internal standard in NMR spectroscopy. Its chemical shift is conventionally set to 0 ppm. TMS is highly volatile, with a low boiling point (around 26-27°C), which makes it easy to remove from a sample after analysis if necessary. However, this high volatility also contributes to its main drawback: ease of evaporation, which can lead to signal loss or drift over time, especially in experiments where the sample is kept at room temperature or higher for extended periods.

Hexamethyldisiloxane (HMDSO): The Handling Advantage
HMDSO (O[Si(CH3)3]2), CAS 107-46-0, presents a compelling alternative to TMS. While it also displays a singlet near 0 ppm in 1H NMR spectra, its boiling point is significantly higher (around 100-101°C). This lower volatility makes HMDSO considerably easier to handle and less prone to evaporation during sample preparation and acquisition. For NMR experiments conducted over longer durations or in situations where sample integrity is paramount, HMDSO offers greater stability and reliability as a chemical standard.

Why Choose HMDSO?

  • Easier Handling: The lower vapor pressure of HMDSO compared to TMS reduces the risk of loss due to evaporation, ensuring consistent reference point throughout experiments.
  • Stability: It is less volatile and generally more stable under various experimental conditions, providing a more robust internal standard.
  • Broad Applicability: While TMS is widely used, HMDSO is gaining traction, especially in fields where sample handling ease and long-term signal stability are prioritized.
While TMS remains a standard, the practical advantages of HMDSO in terms of handling and stability make it a preferred choice for many modern NMR spectroscopists. When you need to buy Hexamethyldisiloxane for your NMR studies, ensure you source it from a reliable manufacturer like ourselves, guaranteeing the purity and consistency required for accurate spectral calibration.

Sourcing Your NMR Standards
As a dedicated supplier of high-purity organosilicon compounds, we offer both HMDSO and TMS to meet your diverse analytical needs. Whether you're performing routine spectroscopy or specialized research, having a reliable source for these essential standards is key. Our commitment to quality ensures you receive products that perform exceptionally. If you're looking to buy Hexamethyldisiloxane for its handling advantages in NMR, or need high-quality TMS, we are here to support your laboratory requirements.