[mrdoovde1]

In an absorption spectrum, the following wavenumbers were measured for the vibronic transitions of a diatomic molecule. Determine the harmonic frequency and the anharmonicity constant (assume that all transitions start from the v" = 0 level of the ground state).
V'    Wavenumber/cm-1
0    35217
1    35633
2    36025
3    36025

Can someone tell me the formula I use and how to calculate this please

Thanks

[rwiew]

You're going to have to show us some attempts at this question yourself first - let's start with the formula, how can we describe the system here?

[mrdoovde1]

You're going to have to show us some attempts at this question yourself first - let's start with the formula, how can we describe the system here?

That's what I don't get. I don't know what formula to use.

[rwiew]

OK, we'll start with the simplest model of a vibration - a harmonic oscillator (in this question we'll have to consider deviation from that model - hence you're being asked for an anharmonicity constant, but harmonic oscillator is a good starting point). I take you must have been taught about the quantum harmonic oscillator and its solutions - what's the formula for the energy level?

[mrdoovde1]

OK, we'll start with the simplest model of a vibration - a harmonic oscillator (in this question we'll have to consider deviation from that model - hence you're being asked for an anharmonicity constant, but harmonic oscillator is a good starting point). I take you must have been taught about the quantum harmonic oscillator and its solutions - what's the formula for the energy level?

We haven't covered too much on it. This question was from a past exam paper I using for revision.

For your question I'm assuming it's: w x h-bar x (n + 1/2) ?