Estimate the spring constant in units of eV/A^2 for the hydrogen (H2) molecule from the potential energy curve shown below, where r is the distance between protons. From the spring constant and the reduced mass m=1/2m(proton), compute the vibrational frequency. This frequency corresponds to infrared light.(adsbygoogle = window.adsbygoogle || []).push({});

http://geocities.com/greenlran/k.jpg

I tried approximating using V(x)~=V(xe)+1/2k(x-xe)^2 , but i end up with an imaginary term for k. I also tried various other things.. to many to list. but any help would be great!

(correct answer: "approximate V(r) near r=0.74A by V(r)= 1/2k(r-.74)^2 - 4.52eV with k~=47eV/A^2. Freq.(vib)=1/(2pi)*sqrt(2k/m(proton))=1.5e4Hz)

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# Homework Help: Small Oscillations

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