All Q from Physical Chemistry Peter Atkins…

All Q from Physical Chemistry Peter Atkins…

All Q from Physical Chemistry Peter Atkins (Author), Julio de Paula (Author)

Interpret the following features of the NMR spectra of hen lysozyme: (a) 14.22
saturation of a proton resonance assigned to the side chain of methionine105
changes the intensities of proton resonances assigned to the side chains of
tryptophan-28 and tyrosine-23; (b) saturation of proton resonances assigned to
tryptophan-28 did not affect the spectrum of tyrosine-23
Two groups of protons have ?=4.0 and ?=5.2 and are interconverted by a 14.2
conformational change of a fluxional molecule. In a 60 MHz spectrometer the
spectrum collapsed into a single line at 280 K but at 300 MHz the collapse did
not occur until the temperature had been raised to300 K. What is the activation
energy of the interconversion
a)Use Table 14.2 to predict the magnetic fields at which (a) 1H, (b) 2H,) 14.6
(c)13C come into resonance at (i) 250 MHz, (ii) 500 MHz