Question

(10) 6. Describe how a reflectron time-of-flight mass analyzer works. Make a diagram in your description. Make sure to label each component in your diagram.

Answer 1

Answer: A mass spectrometer employs ionization and mass analysis of compounds to determine mass, formula and structure of compound. Time of flight is type of analyzer which separates ions without the use of electric and magnetic field instead the separation is done using kinetic energy and velocity of ions. Reflectron is a type of time of flight mass spectrometer. It includes a pulsed ion source, field free region, ion mirror and ion detector. A reflectron effects the distribution of initial kinetic energy of the analyzed ions. In the time of flight set up a refletron is added at the end of filed free region which act as focusing mirror. In the first shortest zone, ions are strongly decelerated and then penetrate a longer second zone where they are progressively slowed down.Using the reflectron, one can substantially diminish a spread of flight times of the ions with the same mass-to-charge ratio (m/z) caused by spread in kinetic energy of these ions measured at the exit from the ion source. An ion entering with a large kinetic energy will have a longer travel distance inside the reflectron than an ion with a low kinetic energy and will thus catch it at a focusing distance where the detector will be set.

T : Field free Puth Ion source Defectos slow ion fost ion o