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oai:figshare.com:article/33825217 2026-09-15T21:39:55Z portal_1197 item_type_3 month_year_09_2026

Data for 35 Cl ‐ 1 H heteronuclear correlation MAS NMR experiments for probing pharmaceutical salts Dinu Iuga (1345257) Emily K. Corlett (8275893) Steven P. Brown (1296819) Chlorides Hydrochloric acid Nuclear magnetic resonance spectroscopy Nuclear magnetic resonance Pharmaceutical chemistry Crystallization Migrated from ePrints Heteronuclear multiple-quantum coherence (HMQC) pulse sequences for establishing heteronuclear correlation in solid-state NMR between 35Cl and 1H atoms in chloride salts under fast (60 kHz) magic-angle spinning (MAS) and at high magnetic field (a 1H Larmor frequency of 850 MHz) are investigated. Specifically, recoupling of the 35Cl - 1H dipolar interaction using rotary resonance recoupling with phase inversion every rotor period or the symmetry based SR421 pulse sequence are compared. In our implementation of the PT (population-transfer)-D-HMQC experiment, the satellite transitions of the 35Cl nuclei are saturated with an off-resonance WURST sweep, at a low nutation frequency, over the second spinning sideband, whereby the WURST pulse must be of the same duration as the recoupling time. Numerical simulations of the 35Cl - 1H MAS D-HMQC experiment performed separately for each crystallite orientation in a powder provide insight into the orientation dependence of changes in the second-order quadrupolar broadened 35Cl MAS NMR lineshape under the application of dipolar recoupling. Two-dimensional 35Cl - 1H PT-D-HMQC MAS NMR spectra are presented for the amino acids glycine·HCl and L-tyrosine·HCl and the pharmaceuticals cimetidine·HCl, amitriptyline·HCl and lidocaine·HCl·H2O. Experimentally observed 35Cl lineshapes are compared with those simulated for 35Cl chemical shift and quadrupolar parameters as calculated using the gauge-including projector-augmented wave (GIPAW) method: the calculated quadrupolar product (PQ) values exceed those measured experimentally by a factor of between 1.3 and 1.9.<br><br>Dataset of: 1. NMR calculations 2. Raw files from NMR experiments 3. Simpson simulation files Detailed description is available in the attached Readme file 2021-07-08T00:00:00Z Dataset Dataset 10.82444/warw.33825217.v1 https://figshare.com/articles/dataset/Data_for_35_Cl_1_H_heteronuclear_correlation_MAS_NMR_experiments_for_probing_pharmaceutical_salts/33825217 CC BY 4.0