Recent crystal growth experiments of GaAs by liquid phase electroepitaxy (LPEE) showed that the application of a static magnetic field enhances significantly the mass transport mechanism of LPEE, known as electromigration, and the growth rate is proportional linearly to the applied magnetic field intensity and increases with the field intensity level. The exceptionally large increase in electromigration was previously predicted from a global continuum model by introducing a magnetic mobility in the constitutive equations for the Ga-As solution, similar to the well-known electric mobility. In this article we provide a thermodynamic interpretation for the magnetic mobility, and the crystal growth kinetics that predicts the experimentally observed magnetic field increase in crystal growth rate. (C) 2007 Elsevier B.V. All rights reserved.