Question
This technique improves resolution for a solid sample because it averages out the effects of chemical shift anisotropies. For 10 points each:
[10m] Name this resolution-increasing technique in which samples are rotated at a namesake value theta for which cosine squared of theta equals one-third.
ANSWER: magic angle spinning [or MAS; accept magic angle turning or MAT]
[10e] MAS can also average out the anisotropy of an effect of this name. A constant named for this phenomenon is subtracted from the atomic number to give the effective nuclear charge acting on a valence electron.
ANSWER: shielding anisotropy [or atomic shielding; or electron shielding; accept screening]
[10h] This technique, which can be used alongside MAS, occurs when the Hartmann-Hahn condition is met. This double resonance technique uses coupling with abundant spins to enhance dilute spins like those from carbon-13.
ANSWER: cross-polarization [prompt on CP]
<Zhang, Chemistry>
Summary
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Data
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