showing 3 related works from this author
Photochemically induced dynamic nuclear polarization of heteronuclear singlet order
2021
Photochemically induced dynamic nuclear polarization (photo-CIDNP) is a method to hyperpolarize nuclear spins using light. In most cases, CIDNP experiments are performed in high magnetic fields and the sample is irradiated by light inside a nuclear magnetic resonance (NMR) spectrometer. Here we demonstrate photo-CIDNP hyperpolarization generated in the Earth's magnetic field and under zero- to ultralow-field (ZULF) conditions. Irradiating a sample containing tetraphenylporphyrin and para-benzoquinone for several seconds with light-emitting diodes produces strong hyperpolarization of 1H and 13C nuclear spins, enhancing the NMR signals more than 200 times. The hyperpolarized spin states at th…
Chapter 23. Singlet Order in Heteronuclear Spin Systems
2020
The concept of heteronuclear Long-Lived spin States (LLSs) is introduced. In the simplest case of a pair of heteronuclei, such states are given by the singlet order of the spin pair, which can be efficiently sustained under Zero or Ultra-Low Field (ZULF) conditions. Here we describe two possible ways of detecting long-lived singlet order of heteronuclei: detection at ZULF conditions and NMR (Nuclear Magnetic Resonance) detection at high field utilising fast field-cycling. A theoretical description of the underlying spin dynamics is presented for both cases; the discussion is supported by experimental examples of LLSs in 13CH groups. The generality of these phenomena is discussed, as well as…
Correlation of high-field and zero- to ultralow-field NMR properties using 2D spectroscopy
2021
The field of zero- to ultralow-field (ZULF) nuclear magnetic resonance (NMR) is currently experiencing a rapid growth, owing to the progress in optical magnetometry, and also attractive features of ZULF NMR, such as low hardware cost and excellent spectral resolution achieved under ZULF conditions. In this work, an approach is proposed and demonstrated for simultaneous acquisition of ZULF-NMR spectra of individual 13C-containing isotopomers of chemical compounds in a complex mixture. The method makes use of fast field cycling, so that the spin evolution takes place at ZULF conditions, whereas signal detection is performed in a high-field NMR spectrometer. This method has excellent sensitivi…