lec 1 Flashcards
what kind of energy is involved in NMR spectroscopy
radio frequency
what does any kind of absorption spectroscopy involve
- molecules move to higher en lvl, excitation by light en
2. molecules move back to lower en lvl, relaxation
what charge does nucleus contain
pos
what is charge / nucleus able to do
spin
how is spin described
quantum spin number (I)
what is quantum spin number of proton and carbon-13
0.5
what is formula for determining the number of potential orientations of nuclei in magnetic fiend
2I + 1
how many potential spin states for nuclei of proton
2
what are 2 potential spin states for nuclei of protons
- beta, high en, opposite to magnetic field
2. alpha, low en, in line with magnetic field
what is delta E
the diff in en bw spin states
what is delta E proportional to
strength of magnetic field
what happens as delta E gets bigger
the more the excess nuclei in alpha spin state
what is spin flip
nuclei from alpha spin state move to beta spin state and vice versa
when does spin flip occur
when radio frequency is equal to delta E
what happens to nuclei that are excited to beta spin state
return to alpha spin state
