Solutions of two paramagnetic ions for use in nuclear magnetic resonance phantoms

The introduction of paramagnetic ions to affect relaxation times has been used in a variety of nuclear magnetic resonance (NMR) applications. All such relaxants used in NMR phantoms to date have consisted of a single paramagnetic ion. The disadvantage of this is that only one relaxation time can be adjusted as desired, either T 1 or T 2 . This study demonstrates that, by properly choosing two paramagnetic ions, it is possible to adjust both T 1 and T 2 independently over a wide range of values. Specifically, solutions of MnCl 2 and NiCl 2 were prepared that simultaneously matched target T 1 and T 2 values to within approximately 6%.