188:. Solving the Schrödinger equation with the Morse potential for the molecule under consideration yields vibrational energy eigenstates with the interesting property that when one calculates transition dipole moments for various vibrational energy level transitions, the transition dipole moment is not zero for the transitions where ∆v=±2,±3,±4, etc. Thus, for real molecules, the allowed transitions are those for which ∆v=±1,±2,±3,±4, etc. The overtone band observed in the
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165:" values of energy. When electromagnetic radiation is shined on a sample, the molecules can absorb energy from the radiation and change their vibrational energy state. However, the molecules can absorb energy from radiation only under certain condition, namely- there should be a change in the
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of the molecule, for transition from the lower to higher energy state, being non-zero which is an essential condition for any transition to take place in the vibrational state of the molecule (due to
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is the spectral band that occurs in a vibrational spectrum of a molecule when the molecule makes a transition from the
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of the molecule when it is vibrating. This change in the electric dipole moment of the molecule leads to the
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Generally, in order to study the vibrational spectra of molecules,
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is one such transition with ∆v=2, from v=0 to v=2 energy state.
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vibrations are assumed to be approximable as simple
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