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I Mass spectrum analysis

  1. Jun 18, 2016 #1
    Hello everyone,

    I'd like to know how to identify the charge and the mass in a mass spectrum. How do I get the mass corresponding to a peak. I know how they are related

    z_1 =\frac{p_2-1}{p_2-p_1}
    M_r = \frac{1}{\frac{1}{p_1-1}-\frac{1}{p_2-1}}

    but do I need a reference mass for a mass-to-tof calibration or?
  2. jcsd
  3. Jun 18, 2016 #2
    sorry, didn't know how to use Latex here ;)
    p=\frac{m}{z}$$ $$
    p_1=\frac{M_r+z_1}{z_1}$$ $$
    p_2=\frac{M_r+(z_1-1)}{(z_1-1)} $$ $$
    z_1 =\frac{p_2-1}{p_2-p_1} $$ $$
    M_r = \frac{1}{\frac{1}{p_1-1}-\frac{1}{p_2-1}}$$
  4. Jun 19, 2016 #3


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    Staff: Mentor

    Welcome to the PF.:smile:

    Could you define your terms, and give us a diagram of the path of the particles as they pass through the fields?

    Also, is this for a schoolwork assignment?
  5. Jun 21, 2016 #4
    schoolwork would be nice, seminar for graduated ;)
    mass $$m$$
    charge $$z$$
    peak in spectrum $$p_i$$
    original mass of ion $$M$$

    What I essentially wanted to ask: Do you need a reference mass (e.g. a bucky ball or a carbon atom) with a known mass for measuring a spectrum of a new molecule or can you gain this information only by some calculation (as mentioned above) out of a spectrum without any reference?
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