Two‐Dimensional Double‐Quantum 2 H NMR Spectroscopy in the Solid State under OMAS Conditions: Correlating 2 H Chemical Shifts with Quasistatic Line Shapes

Solid‐state 2 H NMR spectroscopy is a well‐established and versatile method to study molecular orientation and dynamics in selectively deuterated samples. Herein, we introduce a 2D 2 H double‐quantum (DQ) NMR experiment performed under fast magic‐angle spinning with a slight offset of the magic angle (OMAS). The experiment combines 2 H chemical‐shift resolution with DQ‐filtered quasistatic 2 H line shapes. In this way, it is possible to separate 2 H resonances and to independently determine 2 H quadrupole couplings at multiple sites. While 2 H chemical shifts are resolved in the 2 H DQ dimension, the quadrupole parameters can be obtained from characteristic line shapes which are reintroduced in the second dimension by the magic‐angle offset. The 2D 2 H DQ OMAS experiment is demonstrated on L ‐histidine which was deuterated at multiple sites by recrystallisation from D 2 O.