Angular frequency of an ammonia molecule

In summary, the conversation discusses finding the angular frequency of oscillation between two states of an ammonia molecule when a static electric field is applied. The equation for the total Hamiltonian is provided and simplified, and the value for the angular frequency is calculated using the given values. The result is verified to be correct.
  • #1
yamata1
61
1
Hello
1. Homework Statement

The dipole moment of an ammonia molecule is ##d_0=5*10^{-30} C.m##.If we apply a static electric field of ##\mathcal { E }=1*10^{6 }V*m^{-1}## to an ammonia molecule initially in the state ## |ψG⟩## where the nitrogen molecule is considered to be on the left,we make it oscillate between states ##|ψ+⟩## and ##|ψ−⟩ ##which represent two wavefunctions.What is the angular frequency of oscillation between the two states ?

Homework Equations


In the ##(|ψ+⟩ ,|ψ−⟩)## basis:
##\hat { H } _ { \mathrm { tot. } } = \hat { H } _ { 0 } + \hat { W } = \frac { \hbar \omega _ { 0 } } { 2 } \left( \begin{array} { c c } { - 1 } & { 0 } \\ { 0 } & { 1 } \end{array} \right) - d _ { 0 } \mathcal { E } \left( \begin{array} { l l } { 0 } & { 1 } \\ { 1 } & { 0 } \end{array} \right)##
We can put the hamiltonian in a simple form : ##\hat { H } _ { t o t } = - \frac { \hbar \Omega } { 2 } \left( \begin{array} { c c } { \cos 2 \theta } & { \sin 2 \theta } \\ { \sin 2 \theta } & { - \cos 2 \theta } \end{array} \right)## with ##\tan 2 \theta = \frac { 2 d _ { 0 } \mathcal { E } } { \hbar \omega _ { 0 } } \quad - \pi / 4 < \theta < \pi / 4## et ##\omega _ { 0 }=160*10^9 Hz##[/B]
##( \frac { \hbar \Omega } { 2 } ) ^ { 2 } = ( \frac { \hbar \omega _ { 0 } } { 2 }) ^ { 2 } + ( d _ { 0 } \mathcal { E } ) ^ { 2 }## so the angular frequency is ##
\Omega=\frac { 2 } { \hbar }\sqrt{( \frac { \hbar \omega _ { 0 } } { 2 }) ^ { 2 } + ( d _ { 0 } \mathcal { E } ) ^ { 2 }}
##

The Attempt at a Solution


By using the given values I find that ##\Omega=188000000000 \; rad.s^{-1}##.Is it correct ?

Thank you[/B]
 
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  • #2
Is ω0 in Hz or rad/s?
 

FAQ: Angular frequency of an ammonia molecule

What is the angular frequency of an ammonia molecule?

The angular frequency of an ammonia molecule is the rate at which the molecule rotates around its own axis. It is measured in units of radians per second (rad/s).

How is the angular frequency of an ammonia molecule calculated?

The angular frequency of an ammonia molecule can be calculated by dividing the rotational constant (B) by the reduced mass (μ) of the molecule, using the formula ω = B/μ. The rotational constant and reduced mass can be obtained experimentally or from theoretical calculations.

What factors affect the angular frequency of an ammonia molecule?

The angular frequency of an ammonia molecule is primarily affected by its moment of inertia, which is dependent on the molecule's shape and mass distribution. Other factors that may affect the angular frequency include temperature, pressure, and any external forces acting on the molecule.

Why is the angular frequency of an ammonia molecule important?

The angular frequency of an ammonia molecule is important because it provides valuable information about the molecule's structure and behavior. It is also used in spectroscopic techniques to identify and characterize different molecules, as each molecule has a unique angular frequency.

How does the angular frequency of an ammonia molecule relate to its energy levels?

The angular frequency of an ammonia molecule is directly related to its energy levels. As the molecule rotates, it gains kinetic energy, and the higher the angular frequency, the higher the energy level. This relationship is described by the equation E=ℏω, where E is the energy level, ℏ is Planck's constant divided by 2π, and ω is the angular frequency.

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