The simple harmonic oscillator model for vibrational modes can be refined by an improved version (suggested by Brendel) that accounts for local variations in disordered systems by a Gauss-distribution of resonance frequencies:

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Depending on the values of the width s of the Gauss-distribution and the damping constant Ωτ  any line shape between a Gaussian  and a Lorentzian can be achieved. Due to this flexibility the 'Brendel' model has turned out to be very useful in many cases.

The four quantities of Brendel oscillators can be set in the following SCOUT dialog: