Opportunity at National Institute of Standards and Technology NIST
High-Accuracy Measurements on Complex Mixtures with NMR Spectroscopy: Applications to Refrigeration, Forensic Science, Hydrogen Storage and Carbon Capture
Material Measurement Laboratory, Applied Chemicals and Materials Division
Please note: This Agency only participates in the February and August reviews.
|Kavita M Jeerage
|Tara Marie Lovestead
|Jason A Widegren
Nuclear magnetic resonance (NMR) spectroscopy has several important advantages for quantitative mixture analysis: mole ratios of mixture components can be obtained without calibration; narrow, symmetric peaks and flat baselines are readily obtained for most samples; signal averaging can be used to optimize signal-to-noise ratios; a wide range of molecular masses is accessible; and the sample can be gas, liquid, or solid. Despite these advantages, the use of NMR for high-accuracy mixture analysis has been largely limited to one-dimensional 1H NMR spectroscopy on liquid-phase samples at ambient pressure. Our goal is to broaden the use of NMR spectroscopy for composition measurements on complex mixtures that are important for real-world applications.
We seek proposals related to any aspect of complex mixture analysis by NMR spectroscopy. We are particularly interested in the application of NMR spectroscopy to the analysis of mixtures with multiple phases. For example, high-accuracy vapor-liquid equilibria measurements on refrigerant mixtures (e.g., R-410a) or carbon-capture systems could lead to enormous cost savings. Vapor-solid and liquid-liquid equilibria measurements are also of interest. A few salient examples of such systems include the study of carbon sequestration in building materials such as cement and concrete, the characterization of hydrogen-storage materials and gas-separation membranes, and the investigation of vapor partitioning for forensic science applications such as fire debris analysis. The underlying metrology of NMR-based mixture measurements is also of special interest for us. Potential project areas include the design and development of systems that allow for careful control and measurement of the temperature and pressure of the sample; the development of peak-deconvolution algorithms that can account for peak asymmetry due to imperfect shims; the use of spatially selective or multidimensional NMR methods; and the development of reference materials, especially for gas-phase mixture analysis. A 600 MHz NMR spectrometer will be at the disposal of the researcher, along with a variety of other analytical methods.
Nuclear magnetic resonance spectroscopy; NMR; Quantitative NMR; qNMR; Standard reference materials; Multidimensional NMR; Spatially selective NMR; Gas-phase mixtures; Vapor-liquid equilibria; Vapor-solid equilibria; Liquid-liquid equilibria
Open to U.S. citizens
Open to Postdoctoral applicants