The dilute fluid phase of model globular proteins is studied. The model
possesses a fluid-fluid transition buried within the fluid-crystal coexistence
region, as do some globular proteins. If this fluid-fluid transition is not
buried deep inside the fluid-crystal coexistence region the crystalline phase
does not nucleate within the dilute fluid. We link this lack of nucleation of
the crystal to the interactions in our model and speculate that similar
interactions between globular proteins are responsible for the difficulty found
in crystallising many globular proteins.Comment: 11 pages, 4 figure