Lanthanide Ions as Probes in Antibodies

Burton, Dennis R.; Forsén, Sture; Karlström, Gunnar; Willan, Keith J.; Wright, Cody Elvin; Dwek, Raymond A.

doi:10.1007/978-1-4613-4006-5_15

Cited by 2 publications

(1 citation statement)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The latter relaxation rates may be expressed using Redfield theory in terms of molecular parameters. 1,[5][6][7][8] However, under nonextreme narrowing conditions (SϾ1) ͑when well defined electron spin relaxation rates do not exist͒ it is also possible to derive closed form expressions for these spectral densities s DD . 9 The MSBM theory ͓Eqs.…”

Section: ͑3͒mentioning

confidence: 99%

A low-field paramagnetic nuclear spin relaxation theory

Westlund

1998

The Journal of Chemical Physics

View full text Add to dashboard Cite

Articles you may be interested inTheory for cross effect dynamic nuclear polarization under magic-angle spinning in solid state nuclear magnetic resonance: The importance of level crossings J. Chem. Phys. 137, 084508 (2012); 10.1063/1.4747449The mechanism of paramagnetic NMR relaxation produced by Mn(II): Role of orthorhombic and fourth-order zero field splitting terms Electron spin relaxation due to reorientation of a permanent zero field splitting tensor Static zero field splitting effects on the electronic relaxation of paramagnetic metal ion complexes in solution A low-field theory of paramagnetically enhanced proton spin-lattice relaxation is developed resulting in closed analytical expressions. The theory describes paramagnetically enhanced water proton spin-lattice relaxation in complexes of transition metal ions with electron spin quantum number Sϭ1. In the low-field regime the electron spin system is dominated by a static or permanent zero-field splitting interaction which is much larger than the Zeeman interaction. The electron spin is thus quantized in the molecular fixed principal frame of the static ZFS-interaction rather than in the laboratory fixed frame. In the molecular fixed frame the zero-field splitting Hamiltonian is characterized by an axial parameter (D) and a rhombic parameter (E). It is shown how the relative magnitude of D and E strongly influence the magnitude of the paramagnetically enhanced proton spin lattice relaxation rate. In describing electron spin relaxation in the molecular fixed frame, we consider a transient ZFS-interaction and a reorientation modulated Zeeman interaction as the two main relaxation mechanisms. Then, using Redfield theory we derive expressions for the relevant electron spin relaxation rates in terms of spectral densities. In contrast to the Zeeman or high field regime, the electron spin system in the low field limit does not have a permanent magnetic moment. The lack of this magnetic moment implies that electron spin-lattice relaxation processes do not influence the paramagnetically enhanced proton spin-lattice relaxation rates. Instead three spin-spin relaxation rates determine the enhanced proton spin-lattice relaxation profile. We express the electron spin-spin relaxation rates in terms of spectral densities determined by the mean square value of the transient zero-field splitting interaction, its characteristic correlation time, and the reorientational correlation time of rank 1.

show abstract