Aluminium-27 nuclear magnetic resonance studies of heteropolyanions containing aluminium as heteroatom

Abstract

The preparation of [AlW₁₂O₄₀]^5– and of [AlMo₆O₂₁]^3– has been monitored by ²⁷Al n.m.r. spectroscopy. It is possible to distinguish between aluminium in octahedral and tetrahedral environments. The preparation of [AlW₁₂O₄₀]^5– gives rise to four species containing aluminium of which one is the desired product, one is probably a protonated form of it, and one may be the 2 : 18 (Al : W) anion.