A theoretical basis for spontaneous polarization transfer in non-hydrogenative parahydrogen-induced polarization

TY - JOUR

T1 - A theoretical basis for spontaneous polarization transfer in non-hydrogenative parahydrogen-induced polarization

AU - Adams, Ralph W.

AU - Duckett, Simon B.

AU - Green, Richard A.

AU - Williamson, David C.

AU - Green, Gary G. R.

PY - 2009/11/21

Y1 - 2009/11/21

N2 - When parahydrogen adds to a metal template containing a substrate of interest, the substrate and parahydrogen become coupled, and polarization is shared between the two without the incorporation of the parahydrogen into the substrate. A mechanism for this polarization transfer is presented in which the transfer is propagated through the scalar couplings. At zero field, polarization is transferred between two-, three-, and four-spin zero quantum states, but no single spin magnetization is created. The interplay between the chemical shift evolution and the evolution under scalar coupling at non-zero field generates additional longitudinal spin order and now includes single spin longitudinal z-magnetization. The additional chemical shift interaction introduces a field dependency to the nuclear spin states of the polarized substrate. The net effect of the polarization field strength on the resultant nuclear spin states is shown to be predictable but complex.

AB - When parahydrogen adds to a metal template containing a substrate of interest, the substrate and parahydrogen become coupled, and polarization is shared between the two without the incorporation of the parahydrogen into the substrate. A mechanism for this polarization transfer is presented in which the transfer is propagated through the scalar couplings. At zero field, polarization is transferred between two-, three-, and four-spin zero quantum states, but no single spin magnetization is created. The interplay between the chemical shift evolution and the evolution under scalar coupling at non-zero field generates additional longitudinal spin order and now includes single spin longitudinal z-magnetization. The additional chemical shift interaction introduces a field dependency to the nuclear spin states of the polarized substrate. The net effect of the polarization field strength on the resultant nuclear spin states is shown to be predictable but complex.

KW - chemical shift

KW - hydrogen

KW - magnetisation

KW - NUCLEAR-SPIN STATES

KW - LONG-LIVED STATES

KW - SOLUTION NMR

KW - MAGNETIC-FIELD

KW - 4-SPIN SYSTEMS

KW - HYPERPOLARIZATION

KW - MOLECULES

KW - RESONANCE

KW - ALIGNMENT

KW - 3-SPIN

UR - http://www.scopus.com/inward/record.url?scp=70450273276&partnerID=8YFLogxK

U2 - 10.1063/1.3254386

DO - 10.1063/1.3254386

M3 - Article

SN - 0021-9606

VL - 131

SP - 1

EP - 15

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

IS - 19

M1 - 194505

ER -