Molecular beam magnetic resonance of closed shell molecules

Molecular beam magnetic resonance of closed shell molecules 

D2 and HD in their X E+ ground states (a) Principles of molecular beam magnetic resonance 

Now consider the addition of a homogeneous C field, of magnitude B, situated symmetrically between the A and B fields. This does not affect the trajectories of any molecules, but does remove the degeneracy of levels with different M/ values. The further addition of an oscillating magnetic field of frequency v, applied perpendicular to the static field C, will induce transitions between states differing in M/ by 1 if the resonance condition, 

Many variants of the experiment described in figure 8.1 have been performed, and we shall encounter some of them later in this chapter. Perhaps the most important variant is that it is often possible to arrange the state selection so that resonant transitions result in an increase in the detected beam flux, ideally against a very low off-resonance background. This is known as the flop-in mode of detection, and it can be very sensitive. Again we shall meet examples of this later. 

The pioneering experiments on H2, HD and D2 were performed by Kellogg, Rabi, Ramsey and Zacharias in 1939 [3], Their principal objectives were to determine the magnetic moments of the proton and deuteron, and the electric quadrupole moment of the deuteron. The sorry events of 1939 to 1945 brought the work to an untimely 

The effective Hamiltonian for H2 in its E + ground state may be written as the sum of five terms  

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Molecular beam magnetic resonance of closed shell molecules [1 375... 

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