A ¹⁰B NMR study of tetrahedral borons in ring structured borates

¹⁰B NMR and a newly modified version of the SpectraFit automatic fitting program have been employed to determine the intermediate range placement of tetrahedral borons in various borate rings. Each tetrahedral boron site was characterised by a set of quadrupole parameters: the quadrupole coupling constant, C_Q, the asymmetry parameter, η, and their respective standard deviations, σ_CQ and σ_η. The latest version of SpectraFit has been implemented in parallel on a computer cluster using message passing interface libraries and this has allowed for a large increase in speed and accuracy. We used this version to reexamine ¹⁰B NMR spectra from amorphous caesium diborate, amorphous caesium triborate, crystalline caesium triborate (Cs₂O.3B₂O₃), and crystalline potassium diborate (K₂O.2B₂O₃). The results lead us to believe that the intermediate range order of the tetrahedral boron structures can be found.