It causes stretching and scissoring of bonds and gives a signal when the dipole moment of a molecule changes.
One form of this procedure can be used to determine the average orientation of α-helices and β-sheets in membranes. That form of this procedure often uses zinc selenide or geranium and creates an evanescent wave which extends out of that crystal into the target material. That method, which investigates molecular motion on a picosecond scale and uses (*) attenuated total reflectance, is the Fourier Transform type. It causes stretching and scissoring of bonds and gives a signal when the dipole moment of a molecule changes. Often conducted using salt plates or potassium bromide, for 10 points, name this form of spectroscopy in which absorption of light by molecular vibrations produces a fingerprint region.
One form of this procedure can be used to determine the average orientation of α-helices and β-sheets in membranes.
IR Spectroscopy [accept FTIR or Fourier Transform IR until "salt plates"]