Round 6: Tossup 1
The sensitivity of this technique is improved by employing CryoProbes with continuous liquid helium streams. The DISPEL method is applied during this technique to remove “satellites” shouldering primary signals. Chromium(III) acac (“ay-cack”) is used in this technique as a relaxation agent for more rapid scans. One type of this technique applies 45-, 90-, and 135-degree pulses on the sample to induce polarization transfer. Through-space interactions are probed by measuring the Overhauser effect in this technique, one form of which requires concentrated samples due to the low one percent abundance of a natural isotope. Proton decoupling generates singlet peaks with no splitting in this technique’s 13C variant. For 10 points, name this analytical technique that applies a magnetic field on a sample. ■END■
ANSWER: nuclear magnetic resonance spectroscopy [or NMR spectroscopy; accept carbon NMR or carbon-13 NMR or 13C NMR; accept proton NMR or 1H NMR; accept 1-dimensional NMR or 2-dimensional NMR; accept nuclear Overhauser effect spectroscopy or NOE spectroscopy or NOESY until “Overhauser” is read; prompt on spectroscopy; prompt on pulsing or polarization transfer or DEPT until read by asking “what larger technique is that a part of?”]
<McGill C, Chemistry> | Packet F - Chicago C, McGill C, WashU A, Chicago B
= Average correct buzzpoint
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