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Homework Help: Hydrogen molecule as a harmonic oscillator

  1. Mar 20, 2007 #1
    1. The problem statement, all variables and given/known data
    The covalent bond between the two protons in the H2 molecule can be modelled by a harmonic spring with a spring constant k = 1100 N/m.

    a. What is the zero point energy of the H2 molecule as a harmonic oscillator?

    b. What is the energy of the first excited state?

    [tex]m_{p}=1.6726*10^-27 kg[/tex]

    [tex]k=1100N/m[/tex]

    2. Relevant equations
    [tex]m=\frac{m_{p}}{2}[/tex]

    [tex]\omega=\sqrt{\frac{k}{m}[/tex]

    [tex]E=(n+\frac{1}{2})\hbar\omega[/tex]

    3. The attempt at a solution

    [tex]\omega=\sqrt{\frac{1200}{8.363*10^-28}[/tex]

    a. [tex]E_{0}=\frac{1}{2}\hbar\omega=6.047J*10^-20J[/tex] this is CORRECT

    b. ??[tex]E_{1}=\frac{3}{2}\hbar\omega=1.814*10^-19J[/tex] ?? this is INCORRECT

    i don't understand why b. is incorrect but a. is correct. i thought the only difference would be the number for n. what am i doing wrong? can anyone help please?
     
    Last edited: Mar 20, 2007
  2. jcsd
  3. Mar 20, 2007 #2

    Astronuc

    User Avatar
    Staff Emeritus
    Science Advisor

    Try using /tex instead of \tex in [\tex].
     
  4. Mar 20, 2007 #3
    thanks. i don't use that coding often. it should all be fixed now
     
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