| Abstract
| - The incorporation of moderate amounts of Ni(II), Co(II), Fe(II/III), and Mn(II/III) into aluminophosphatezeotype AlPO4-34 and Fe(II/III) into aluminophosphate zeotype AlPO4-36 was studied by broadline 31P NMR.The technique provided direct evidence on isomorphous substitution of framework aluminum by transitionmetals and allowed us to determine the extent of the substitution. 31P NMR proved to be complementary toother spectroscopic techniques such as X-ray absorption spectroscopy (XAS), Mössbauer, electron paramagneticresonance (EPR), and electron nuclear double resonance (ENDOR) spectroscopies. The position of the NMRsignal belonging to phosphorus in the P(OAl)3(OMe) environment depended mostly on the magnitude of thehyperfine interaction between a phosphorus nucleus and an unpaired electron, which was delocalized fromthe transition metal atom Me by covalent bonding. The width of the NMR signal was dominated by dipolarcoupling among phosphorus nuclei and nearest paramagnetic centers. In addition, broadline NMR ofethylenediamine-templated manganese phosphate (C2H10N2)[Mn2(HPO4)3(H2O)], which was used as a modelcompund, showed that on the basis of line positions and line widths different 31P signals could easily beassigned to different phosphorus crystallographic sites. The technique could thus be applied to extract valuablestructural information about metal phosphates as well.
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