Combination Bands
As mentioned above, combination bands involve changes in vibrational quantum numbers of more than one normal mode. These transitions are forbidden by harmonic oscillator selection rules, but are observed in vibrational spectra of real systems due to anharmonic couplings of normal modes. Combination bands typically have weak spectral intensities, but can become quite intense in cases where the anharmonicity of the vibrational potential is large. Broadly speaking, there are two types of combination bands.
Read more about this topic: Hot Band
Famous quotes containing the words combination and/or bands:
“[N]o combination of dictator countries of Europe and Asia will halt us in the path we see ahead for ourselves and for democracy.... The people of the United States ... reject the doctrine of appeasement.”
—Franklin D. Roosevelt (1882–1945)
“While they were there, the time came for her to deliver her child. And she gave birth to her firstborn son and wrapped him in bands of cloth, and laid him in a manger, because there was no place for them in the inn.”
—Bible: New Testament, Luke 2:6,7.