Mixed‐Valence Compounds as Polarizing Agents for Overhauser Dynamic Nuclear Polarization in Solids**
نویسندگان
چکیده
Herein, we investigate a novel set of polarizing agents—mixed-valence compounds—by theoretical and experimental methods demonstrate their performance in high-field dynamic nuclear polarization (DNP) NMR experiments the solid state. Mixed-valence compounds constitute group molecules which molecular mobility persists even solids. Consequently, such agents can be used to perform Overhauser-DNP state, with favorable conditions for formation at ultra-high magnetic fields.
منابع مشابه
Hybrid polarizing solids for pure hyperpolarized liquids through dissolution dynamic nuclear polarization.
Hyperpolarization of substrates for magnetic resonance spectroscopy (MRS) and imaging (MRI) by dissolution dynamic nuclear polarization (D-DNP) usually involves saturating the ESR transitions of polarizing agents (PAs; e.g., persistent radicals embedded in frozen glassy matrices). This approach has shown enormous potential to achieve greatly enhanced nuclear spin polarization, but the presence ...
متن کاملDynamic nuclear polarization and spin-diffusion in non-conducting solids
Microwave irradiation of a coupled electron-nuclear spin system can facilitate a transfer of polarization from the electron to the nuclear spin. In dielectric materials dynamic nuclear polarization (DNP) typically occurs via the solid effect,thermal mixing or the cross effect. In these systems the electron spins are localized and the non-equilibrium polarization of the bulk nuclei is generated ...
متن کاملTheory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids.
Dynamic nuclear polarization (DNP) is a powerful method to enhance sensitivity especially of solid-state magic-angle spinning (MAS) NMR by up to several orders of magnitude. The increased interest both from a practical as well as theoretical viewpoint has spawned several fields of active research such as the development of new polarizing agents with improved or unique properties and description...
متن کاملTOTAPOL: a biradical polarizing agent for dynamic nuclear polarization experiments in aqueous media.
In a previous publication, we described the use of biradicals, in that case two TEMPO molecules tethered by an ethylene glycol chain of variable length, as polarizing agents for microwave driven dynamic nuclear polarization (DNP) experiments. The use of biradicals in place of monomeric paramagnetic centers such as TEMPO yields enhancements that are a factor of approximately 4 larger (epsilon ap...
متن کاملOverhauser Geomagnetic Sensor Based on the Dynamic Nuclear Polarization Effect for Magnetic Prospecting
Based on the dynamic nuclear polarization (DNP) effect, an alternative design of an Overhauser geomagnetic sensor is presented that enhances the proton polarization and increases the amplitude of the free induction decay (FID) signal. The short-pulse method is adopted to rotate the enhanced proton magnetization into the plane of precession to create an FID signal. To reduce the negative effect ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Angewandte Chemie
سال: 2021
ISSN: ['1521-3773', '1433-7851', '0570-0833']
DOI: https://doi.org/10.1002/anie.202103215