Towards this end, solid state 69/71 Ga solid-stateNMR, would be the method of choice to extract coordination geometry, ultimately providing insights into the immediate coordination sphere of the Ga sites within a material. In most instances, Ga NMR is used to identify the geometry and distribution of Ga sites on the basis of chemical shift alone (in an analogous fashion to that employed for Al NMR). For example, hexa-coordinate Ga III sites ( [6]-Ga) are expected to fall within the chemical shift range of 0-50 ppm, with penta-( [5]-Ga) and tetra-coordinate ( [4]-Ga) sites having chemical shift in the 50-100 ppm and 75-250 ppm range, respectively However, direct insights into the precise structure and coordination environment of surface sites are challenging to extract, not least because the dominant signals arising from bulk structures are typically associated with lower quadrupolar coupling constants (CQ) and are thereby more easily detected.