Moving from the dry zeolite model to one with one water bound to BAS, the chemical shift behaves inconsistently and is highly dependent on the local structural environment around the individual T-site. However, a consistent increase in chemical shift is observed when the water loading is increased from 1 to 2 molecules per unit cell. This change is likely due to the decrease in the Al-O bond length associated with the addition of the second water molecule. This additional water molecule interacts with both the BAS proton and the other Al-adjacent framework oxygen atoms, allowing for an intermittent proton transfer, which leads to shortening of the average Al-O bond length, resulting in a higher chemical shift. The average Al-O bond length variation is approximately 0.005 Å, which corresponds to a change in chemical shift of about 1 ppm according to equation 5 (see Table in ESI † for more details). A similar mechanism accounts for the general decrease in chemical shift observed when increasing the water loading from 2 to 17 molecules per unit cell. Upon increasing the water loading further from 2 to 17 molecules, the additional water molecules fully solvate the BAS proton, with the proton removed rather far from the framework, effectively reducing the direct interaction between protonated water cluster (the hydrogen atoms) and the framework (oxygen atoms) at the nearby Al-center. This decreased interaction leads to larger T-O-T angles and smaller Al-O bond lengths, which when combined, result in a lower chemical shift. The structural characteristics and their effects on chemical shift are described in detail in Section S7 †. These results demonstrate that water loading significantly affects the predicted chemical shift values (by up to 2-3 ppm), making it a crucial factor to include in calculations. Note also, that the T9 site consistently exhibits the highest chemical shift values, which can be attributed to its T-O-T angle being the smallest among the T-sites (see Table in ESI †). Interestingly, this is is not observed in the locally optimized structure of the zeolite, rather it is a consequence of the dynamical sampling.