title: Accessing long lived (1)H states via (2)H couplings.
abstract: In this paper we demonstrate long-lived states involving a pair of chemically equivalent protons, with lifetimes ∼30 times T1 up to a total lifetime of ∼117s at high field (8.45T). This is demonstrated on trans-ethylene-d2 in solution, where magnetic inequivalence gives access to the long-lived states. It is shown that the remaining J-coupling between the two quadrupolar deuterium spins, JQQ, splits the conditions for optimally generating proton singlet states. Detailed simulations of the spin evolution are performed, shedding light on the coherent evolution during singlet-triplet conversion as well as on the incoherent evolution that causes relaxation. Subsequently, the simulations are compared with experimental results validating the theoretical insights. Possible applications include storage of hyperpolarization in the proton long-lived state. Of particular interest may be utilization of parahydrogen induced polarization to directly induce the examined long-lived states.
authors.affiliation: Department of Chemistry, Duke University, Durham, NC 27708, United States.
authors.forename: Zijian
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Department of Physics, Duke University, Durham, NC 27708, United States.
authors.forename: Kevin
authors.initials: K
authors.lastname: Claytor
authors.affiliation: Departments of Chemistry, Physics, Radiology and Biomedical Engineering, Duke University, Durham, NC 27708, United States.
authors.forename: Warren S
authors.initials: WS
authors.lastname: Warren
authors.affiliation: Department of Chemistry, Duke University, Durham, NC 27708, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Theis
keywords: Deuterium; Ethylene; Long lived states; Solution NMR