On the Landau-de Gennes elastic energy of constrained biaxial nematics

This paper continues our investigation on the properties of the Landau-de Gennes elastic free-energy for constrained biaxial nematic systems started in Mucci-Nicolodi, ARMA 206 (2012), 853-884. The principal aim of the paper is to discuss the question of coercivity for the most common four-elastic-constant form of the Landau-de Gennes elastic free-energy and the corresponding energy minimization problem