We also performed similar 1 H{ 35 Cl} DE-RESPDOR experiments on transplatin to confirm the that this method provides accurate measurements of the Cl CQ. Excellent agreement was observed between the values of Cl CQ determined with DE-RESPDOR and WURST-CPMG (Figure ). The 35 Cl CT NMR spectrum of transplatin was acquired in just under 30 minutes with RESPDOR as compared to 3 hours for the static WURST-CPMG experiment. We note that in all 1 H{ 35 Cl} DE-RESPDOR experiments there is significant 1 H NMR signal dephasing even when the Cl offset is off-resonance from the CT pattern. This dephasing arises due to saturation of the satellite transitions. To the best of our knowledge, this is the first demonstration of indirect detection of wideline spin I = 3/2 CT quadrupolar powder patterns which are more than 1 MHz in breadth. Further investigation of RESPDOR and its generality for indirect detection of I = 3/2 nuclei are underway. With knowledge of the Cl CQ, the 1 H{ 35 Cl} DE-RESPDOR dephasing curve for the Si-NS can be modelled (Figure ). To accurately simulate the dephasing curve, we built 20 Si-NS structural models, each consisting of two layers stacked on top of each other (Figure ). A Monte Carlo procedure was used to randomize the Cl positions based on the 20 % SiSi3Cl population determined from direct excitation Si NMR spectra and the Cl natural abundance of 75 % (Figure ). In these models, we considered only the central H atom (colored red in Figure ) and calculate the internuclear distances between this H atom and all Cl atoms (Figure ). Multi-spin 1 H-35 Cln (n = 1 -3) numerical simulations were performed for all 1 H- Cl spin pairs within a 5 Å distance (Figure ). Longer-range 1 H- Cl dipolar couplings were accounted for by calculating the root sum square of the dipolar coupling constants for 1 H- Cl spin pairs with a distance > 5 Å and running a twospin 1 H-35 Cl numerical simulation (see Supporting Information for more details about the fitting procedure). We then averaged over the ensemble of the multi-spin numerical simulations for all 20 structures to obtain a curve that represents a random distribution of SiSi3Cl species within Si-NS. Inclusion of long-range couplings is crucial to reproduce signal dephasing at recoupling durations longer than 3 ms (Figure ). The shape of the dephasing curve is sensitive to the Si-Si interlayer spacing because interlayer distance is inversely correlated to inter-sheet 1 H-