Silicon-29 multiple quantum filtered n.m.r. spectroscopic evidence for the presence of only six single site silicate anions in a concentrated potassium silicate solution

Silicon-29 multiple quantum filtered n.m.r. spectroscopy of a (nominally) 1.5 M, 1:1 (K:Si), 29Si isotopically enriched potassium silicate solution shows that only six ‘single site’ silicate anion structures are present, these being the monomer, dimer, cyclic trimer, cyclic tetramer, prismatic hexamer, and, perhaps, the tetrahedral tetramer.