A form of solution-phase Raman spectro·scopy named for this molecular property reports a value called C·I·D. This quantity is unexpectedly zero for the molecule N-butyl·ethyl-N-hexyl-N-propyl·methane. Greater values for this property of a cholesteric (“COAL-uh-steer-ick”) mesogen allow proportionally thinner films to be used in LCDs. Food scientists measure this property as a quality check on the concentration of sugar in syrup. This quantity is traditionally reported at the sodium D line, but since it’s the Kramers–Kronig transform of ellipticity, its dispersion is reported by circular di·chroism. Specific values for this quantity are symbolized by an alpha in brackets. To indicate the sign of this quantity, IUPAC (“I-U-pack”) now prefers pluses and minuses to the archaic prefixes D and L. For 10 points, enantio·meric excess is calculated by using a polarimeter to measure what angle, which is only nonzero for chiral molecules? ■END■
ANSWER: optical rotation [or OR; or specific optical rotation angle; or specific rotation angle; or optical activity or specific optical activity; or OA; or optical rotatory power; or optical rotatory dispersion or ORD; accept any answer that indicates a change OR difference OR rotation in the polarization of polarized light; prompt on rotation; reject “chirality”; reject “chiral angle”; reject “polarization” without any explicit indication of a change or difference]
<Chemistry>
= Average correct buzz position