T9F and 45Sc nuclear spin relaxation for the hexafluoroscandate, hexafluorotitanate, and hexafluorogermanate ions in aqueous solution

Abstract

19F NMR spectra of aqueous solutions containing the 48TiF 6 2−− 49TiF 6 2− and 74GeF 6 2−− 73GeF 6 2− ions and 45Sc NMR spectra of an aqueous solution containing 45ScF 6 3− ion are reported for a range of temperatures. Computer fitting of the observed lineshapes shows that both quadrupole-induced transitions between the spin states of a high-spin nucleus and chemical exchange of the fluorine atoms contribute to the lineshapes. The quadrupole coupling constants were estimated to be 4.5 MHz for 49TiF 6 2−, 5.8 MHz for 73GeF 6 2−, and 9.5 MHz for 45ScF 6 − ions.