# Symmetric Top Orbital Magnetic Transition Moment

This is appropriate for a magnetic dipole transition moment
carried by the electronic orbital angular momentum. In principle
the Hamiltonian for this interaction of the electron orbital
magnetic moment with an external magnetic field is:

g_{L}μ_{B}B.L

Degenerate states in a symmetric top can be
thought of as having approximately one unit of angular momentum.
To allow for the most general possible interactions, the *l*
dependence is not included in evaluating the matrix element, and
the Strength
parameter will be essentially *g*_{L}*l*.
See MNR Ashfold, RN Dixon, N Little, RS Stickland and CM Western,
*J. Chem. Phys.* **89** 1754 (1988) for an example
application.

## Settings

Rank |
Rank of transition - 1 for a normal magnetic dipole
transition. |

Component |
Projection quantum number of transition moment - 0 for a
parallel transition, 1 for a perpendicular transition. This
gives the selection rule on the vibronic angular momentum, *l.* |

## Parameters

Strength |
Transition (dipole) moment in units of the Bohr
magneton. Note that the relative intensity
is proportional to the square of this value. |